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General FAQ on digital photography. Color and light. What about the flash

To store pictures in the camera, storage devices are indispensable. And no matter what they say about the fact that in recent years memory has fallen several times in price, it is still quite expensive. No one complains about the "extra" memory, everyone only talks about its lack. Manufacturers usually do not spoil us with the amount of memory built into the camera, and memory has to be bought in ninety-nine cases out of a hundred. After all, only eight to twelve pictures in JPEG format can fit on a standard eight-megabyte card, and even less in an almost incompressible TIFF format. Agree that it is extremely inconvenient to transfer to a computer or keychain with flash memory every six or ten shots.

Most cameras now have a removable flash memory that stores information without consuming power and, in addition, allows you to connect a portable mass storage device. If the removable memory card is completely filled with images, then you can simply remove it from the camera and insert another module in its place or continue shooting with the built-in memory. Removable memory card is placed in a special compartment digital camera, or, more correctly, in the slot. Each type of media has its own slot design - you cannot insert a memory card that the camera does not support into it.

Most slots are designed to prevent the card from being installed incorrectly (eg upside down). The cameras of most models usually “see” only one of the two available memory cards at a time. If a removable card is inserted into the slot, the camera "forgets" about the existence of the built-in memory. If there is no free space left on the removable card, but you want to shoot more and more, you should remove the card from the slot - then the camera will see the free built-in memory. Comparing the advantages of digital cameras, experts pay attention to the type of memory used. It is always useful to know how compatible the camera's memory is with other devices and whether the cheapness of the "brains" will turn out to be expensive or even a hindrance in operation. Let's list the information storage devices known today, used in digital cameras.

For laptop owners, PC Card ATA, or, as it is also called by the name of the slot, PCMCIA is best suited. Such a connector in laptops, as a rule, is available. Such a card is used to store large amounts of data (up to 1 GB) and is used as an external medium, depending on the type, in photo and video cameras and in laptops. These cards are similar in size and shape to a thick business card. PCMCIA cards are commonly used in large cameras that are close to professional in performance.
Occasionally, digital cameras use Mini Card devices. They are not very reliable. In addition, their data reading speed is quite low. But they consume little energy and have small dimensions: 38x33x3.5 mm. Mini Card devices hold 64 MB of data.

The most common memory format today, Compact Flash, is similar in many ways to PC Cards, but its physical dimensions are much smaller. More recently, the development of technology has made it possible to increase its maximum volume to 1 GB. Compact Flash media has no moving parts and consumes relatively low power - from 3.3 to 5 V, which has made these cards super popular with manufacturers of digital photographic equipment. Compact Flash cards are strong and durable. Manufacturers claim that they can store information for at least a hundred years.

Compact and not too expensive, Smart Media Cards - or, as they were called more recently, SSFDC (English short for Solid State Floppy Disk) - have been around since 1997. They are less compatible with digital devices than Compact Flash cards, and here's why. Smart Media Cards do not have a controller found in Compact Flash and other storage devices. So they sort of rely on a controller built into the camera. Smart Media cards have a capacity of up to 128 MB and are 45x37x0.76 mm in size - about the size of a matchbox. In addition to reduced compatibility, they also have other disadvantages: fragility (the life of the carrier is no more than five years), fragility, exposure to external influences and small volume. The latter once seemed sufficient, but today it is quite small compared to that provided by other carriers. To transfer images to a computer from Smart Media cards, a dedicated Smart Media Adapter is required.

Tiny, postage stamp-sized MultiMedia Card (up to 128 MB) is one of the smallest small capacity storage devices. Initially, they were conceived for portable telephones, but their small size and weight, as well as a simple interface and reduced power consumption, attracted the attention of manufacturers of various digital devices. MultiMedia Cards are increasingly being used in "hybrid" devices such as digital cameras with built-in MP3 players, and (sometimes) in mobile phones that support multimedia messaging. It must be said that the race of manufacturers of RAM for miniaturization led to the appearance of a MultiMedia Card variant called RS-MMC (Reduced Size MultiMedia Card, reduced size multimedia card). The size of RS-MMC has been reduced to 32x24x1.4 mm and is now widely used in smartphones and new generation mobile phones.

Memory Stick from Sony with a maximum capacity of 128 MB looks like a stick of chewing gum and weighs only 4 g, but has not yet found wide application - although the devices for connecting it can be very exotic. Still: closed standard, high price and small volume. Cameras that provide for the use of this type of memory are produced only by Sony Corporation (they are not compatible with other types of memory).

But SD Cards (Secure Digital Cards), which have only recently begun production, seem to be poised to become very popular media. Today they contain only 256 MB of data, which is quite a bit, but the interest in such cards is not at all accidental. The fact is that SD cards are equipped with cryptoprotection against unauthorized copying and protection against accidental erasure and destruction. Such properties have aroused keen interest from both media corporations and consumers, who sometimes wish that pictures from their personal lives could not be copied without their knowledge. SD cards are very small - with dimensions of 24x32x2.1 mm they weigh only 2 g. The SD Card slot also accepts a MultiMedia Card, which makes the "secure" format even more promising. It is also important that SD Cards consume very little energy and are quite durable.

There were even disposable (non-erasable) flash cards from the Shoot & Store series from SanDisk. Their manufacturer believes that the appearance of such media will contribute to a truly massive transition from film to digital. After all, with the advent of disposable memory, the problem of storing images will be solved and the need for a computer will disappear by itself. In terms of cost, disposable flash cards will be comparable to conventional film, and the difference in price is compensated by their reliability and the convenience of choosing frames for printing.

The recently introduced miniature DataPlay data offload disks are quickly gaining popularity because of their low cost: 500 MB of such memory costs only $ 10. DataPlay uses smaller DVD optics and the drive looks like a hard drive. In practice, DataPlay can be called a miniature DVD (33.53x39.5 mm in size). DataPlay has announced plans to release devices with a capacity of 4 GB. Here's just one thing is not good: the DataPlay disc is disposable and does not provide for re-recording. But how cheap!

In digital cameras, even media such as CD-R discs and CD-RWs. Yes, don't be surprised! The CD is inserted into the camera and carries up to 156 MB of recorded data! True, Sony, which produces such an exotic with direct recording of an image on a CD, is still alone on the market: no one else is trying to imitate it.

Now, knowing the advantages and disadvantages of different types of memory, try to evaluate the memory of your camera (or the one you are about to buy) against the backdrop of all this variety of external storage media.

conclusions
When removing the card from the camera for the first time, pay attention to how it is inserted. Reversing the direction of the pins can damage both the card and the camera.
Protect the card from the accumulation of static charges. If you had to remove it from the camera, place it on a metal surface or foil from time to time. Avoid rubbing the card against the fabric.
Be especially careful with the contacts of the card. Avoid scratching or other damage.
Keep in mind that many cards are quite fragile. If you drop the card, you can lose both the data stored on it and the money you spent on it.

Any fairly complex electronic device is a computer in one form or another, since it provides either information processing or some kind of reaction in response to its change. In particular, any film camera that provides automatic calculation of exposure and focusing is equipped with the simplest or most complex (depending on the class) microprocessor - and often more than one. These devices, analyzing information from sensors, focus the lens and calculate the aperture and shutter speed - and a specialized database is used for the latter operation.

And even more so without a computer digital camera, which stores the images themselves as binary information. Moreover, even the set of components of such a camera is quite familiar to any user familiar with the stuffing of a computer. Among the nodes of a digital camera, you can find ROM, RAM, modest power consumption CMOS memory, non-volatile flash memory, hard disk drives (HDD), often called "hard drives", and even such exotic things as floppy drives and CD-drives. RW.

Obviously, most readers are familiar with the purpose of the above devices - all of them, one way or another, serve for operational or long-term data storage. However, the question may arise how these components are used in digital photographic equipment - especially considering the fact that some of them are distinguished by both excellent "gluttony" (in terms of electricity) and impressive dimensions.

In order for the story to go from simple to complex, it is advisable to review chronologically - both regarding the development of the cameras themselves, and regarding the processes taking place in a digital camera.

ROM, RAM and CMOS

So, if we recall the very first amateur digital camera, which appeared in 1990 and was called the Dycam Model 1 (although it was better known as the Logitech FotoMan FM-1), then its internal organization will resemble the most primitive computers of that time. The ROM contains both a set of programs that control the "photographic" part of the programs (that is, exposure calculation algorithms), and utilities that provide image formation based on data coming from the ADC, as well as subsequent information compression.

All programs stored in ROM are loaded into RAM after the camera is turned on. Pictures are also stored here - the Dycam Model 1 did not have non-volatile information storage facilities, and when a pair of "finger-type" batteries, which were the main power source of the camera, were discharged, all the captured frames disappeared. Of course, this state of affairs categorically could not suit users, so the following models of digital photographic equipment already had devices that made it possible to store images indefinitely (or almost indefinitely) for a long time without any energy sources. However, both ROM and RAM were preserved in these cameras - the first type of memory still stored programs, but the functions of the second expanded somewhat.

The fact is that digital cameras have found color. However, this color for each frame had to be restored - interpolated, and for such operations it is necessary to RAM, so the pictures still ended up in RAM, only this time not for storage, but for processing. This processing consisted of the formation of a picture based on the ADC data, color restoration, and information compression. The resulting images were stored in the built-in non-volatile flash memory of the camera.

In RAM, not only image processing was performed. A section of this memory was allocated and assigned to the role of service memory - it stored all the camera settings made by the user. The first models of digital cameras were quite simple, so the resolution, compression ratio and flash mode selected by the user were lost when the camera was turned off - it was not difficult to set these parameters the next time it was turned on. But when the exposure compensation and white balance functions appeared, it was decided to save the settings made by the user in the RAM section allocated for service memory - at least until the next battery change. As the resolution of CCD matrices grew, it became obvious that storing pictures in the built-in flash memory would obviously limit the user in terms of the available number of frames. Therefore, cameras have acquired interchangeable flash memory modules, from which not only users, but also manufacturers have benefited. Firstly, the demand for cameras increased (it became possible to take them on vacation), secondly, a market for memory modules arose, and thirdly, various devices became widespread that allow reading data from a module without using a camera. These devices, called readers, had a wide variety of designs (they will be discussed in more detail below), although they had one feature in common - they provided access to images organized as files.

Accordingly, another load fell on the camera's RAM - it converted the image into one or another file format. The most common are JPEG, TIFF and RAW files. It should also be noted that by the time of the appearance of removable media, some manufacturers began to equip their cameras with the functions of increasing / decreasing the brightness, contrast and clarity of the image, as well as converting the image to black and white. All these transformations were carried out after color restoration and, frankly, much better results could be achieved using specialized image processing software.

Most often, frames are saved in JPEG files. This abbreviation hides the name of the organization (Joint Photographic Experts Group), which has developed a fairly effective information compression algorithm. This algorithm consists of the following steps:

  • converting the image's color space from RGB (which uses shades of red, blue, and green to display all colors) to YUV (where Y is the brightness of the pixel, and U and V are the color data). In this case, first of all, the safety of information about the brightness of the pixel is ensured, and for human vision this is more important than color data.
  • splitting the frame into blocks of 8X8 pixels, followed by a discrete cosine transformation of these blocks, which converts the image into a set of harmonic oscillations with different amplitudes and frequencies.
  • analysis of amplitude-frequency characteristics for the repeatability of color fields, followed by the exclusion of 50 percent of the brightness and 75 percent of the color data.

It is because of the last step that JPEG is classified as a lossy compression algorithm. In other words, even with the minimum compression ratio, it is impossible to completely restore the original image. And at maximum compression ratios, too much of both brightness and color information is lost, and JPEG artifacts are more and more clearly visible in the image - "blurred" borders of contrast areas, splitting the frame into blocks of 8X8 pixels, and so on.

Unlike the JPEG algorithm, the compression used in the TIFF format does not result in data loss. The algorithms used in this case are very similar to those used in archiving programs and provide 100% image recovery. However, TIFF files take up noticeably more space, even compared to JPEG files with minimal compression, while errors in exposure calculation or focusing spoil the frame much more than JPEG artifacts. The conclusion follows from this - you should shoot as many frames as possible and select the most worthy ones, and from this point of view, the JPEG format is preferable.

RAW format files are "casts" from the CCD without any transformations - first of all, color interpolation is not performed. At the same time, uncompressed files take up more space than TIFF files, and their processing on a computer requires specialized and functionally limited software. However, at the moment, most manufacturers provide compression of RAW files, and they often turn out to be more compact than TIFF files. And for greater convenience in further image processing, plug-ins for Adobe Photoshop are released that allow you to use the full power of this package when processing RAW images.

The question arises - "why do you need a RAW format at all?" The fact is that sometimes both the dynamic range of the matrix and its ADC make it possible to obtain an image with a greater color depth than the standard 24 bits used in JPEG and TIFF formats. And just for saving a 30, 36 or 48-bit RAW image is best suited - excess bits can always be used to correct "overexposure" or "underexposure".

Along with the resolution of CCD matrices, their performance also steadily increased. In the end, the speed of reading data from the sensor became such that it became possible to implement the continuous shooting mode, in which the camera takes a series of shots with minimal intervals between them. And since at high resolution even a short series requires a fairly impressive amount of memory, the size of the RAM has grown significantly. Since then, this type of memory has become known as buffer memory. Simultaneously with the continuous shooting mode, the models began to be equipped with the functions of exposure bracketing, exposure lock, multi-zone autofocus and other useful things. At the same time, as the resolution grew, power consumption also increased, so the batteries had to be changed especially often. And every time I had to completely adjust the camera. This state of affairs did not suit the users, as a result, it was decided to use a CMOS memory with a very modest power consumption as a service memory - it actually "was enough for one" tablet "(meaning a watch battery). Experienced readers guessed that the solution was borrowed from the world of personal computers, in which the motherboard settings are also stored in a CMOS memory powered by a "pill".

However, what is good for a computer is not always good for a digital camera. The compartment for the "tablet" took up space in the case, it was necessary to bring a hatch to one of the panels to replace the battery, and the design of the camera as a whole became more complicated. Therefore, a different solution was required, which, in the end, was found.

Flash memory

As already mentioned, the main distinguishing feature of flash memory is its non-volatility - it is able to store information for a very long time without any energy sources. This is similar to ROM, but unlike the latter, flash memory allows modification of the data stored in it. This is achieved by the fact that when reading information, a low voltage is used, and when writing, a high voltage is used.

The combination of these properties has led to the fact that in digital cameras, flash memory has become the main device for long-term storage of images. In early cameras, flash memory was built-in and after it was full, images were uploaded to a personal computer. With increasing file sizes, replaceable memory modules have become widespread, but the built-in flash memory in cameras has also been preserved.

As already mentioned, the use of CMOS tablets as a service memory complicates the design and increases the dimensions. Therefore, it was decided to use the built-in flash memory of the camera as a service one - in this case, the issue of power supply automatically disappeared. Moreover, there was an opportunity to solve two more newly emerging problems.

Firstly, due to the quite understandable "hurriedness" of manufacturers (after all, the market must be conquered), it often turned out that some of the functions did not work quite the way they should. The same problem occurs with computer motherboards and it is "treated" by flashing basic system input / output (BIOS), which for the time being is not stored in ROM, but in flash memory. This solution migrated to digital cameras, and now to correct "inadequate behavior" when calculating exposure or focusing, it is enough to get the latest software "patch" and "impose" it on the camera's firmware stored in flash memory.

Secondly, the increase in the resolution of the matrices had a negative impact on the production volumes - an increasing percentage went into marriage due to the abundance of "sticky" pixels. At the same time, the demand for digital photography continued to grow. Therefore, the rejection standards were made more liberal, and so that users would not be embarrassed by "sticky" pixels, cameras began to be equipped with a mode that scans defective elements of the CCD matrix and stores their coordinates in the service flash memory. And when generating a full-color image, the elements included in the "list of stuck pixels" were excluded from consideration.

Removable Flash Memory Modules

So, by the time the resolution of CCDs approached the megapixel mark, most manufacturers of amateur digital cameras switched to replaceable flash memory modules. However, it should be noted that the initiative to switch to removable storage media belonged to the developers of digital SLRs.

It was in the 1994 Kodak DCS-420 SLR digital cameras that slots for installing PCMCIA cards first appeared. In turn, these flash memory cards were developed even earlier for portable computers by the Personal Computer Memory Card International Association (PCMCIA). The standard recommended by this organization described both the shape and voltage of the connectors and the dimensions of the cards. It was also planned that modems, network cards, SCSI adapters and other devices would be produced in this form factor and using the same connector. The standard was later renamed PC Card.

PCMCIA card

Ultimately, three types of PCMCIA cards emerged. All of them have the same length and width (85.6x54 mm), but their thickness is different: type I is 3.3 mm thick, type II is 5 mm, and type III is 10.5 mm. The cards also differ in supply voltage - 3.3 or 5 volts. Flash memory cards were mainly Types I and II.

Despite the fact that the dimensions of the PCMCIA-slots were more suitable for impressive-sized "DSLRs", a place for them was also found in the cases of some amateur cameras - for example, the Kodak DC-50. However, the CompactFlash standard, which appeared in 1994, which became the development of PCMCIA, achieved much more success.

The appearance of cards of this type became possible due to the increase in the recording density in flash memory chips. As a result, chip sizes were reduced, and SanDisk decided to create a new type of memory card, while maintaining compatibility with the PCMCIA format - although the number of contacts was reduced from 68 to 50, the CompactFlash modules were electrically fully compatible with their predecessors. And for mechanical compliance, a CompactFlash-PCMCIA adapter in the form of a PCMCIA card was enough, into which, due to its small size (43X36X3 mm), new modules were inserted. Well, the entire assembly could be placed in a laptop slot and read images directly into a computer, without using any connecting wires or software to communicate with the camera.



CompactFlash module

Like PCMCIA cards, CompactFlash modules initially differed in supply voltage - 3.3 and 5 volts. Then another difference was added - CompactFlash type II cards appeared, the thickness of which was already 5 mm. Thanks to this, it became possible to significantly increase the capacity of the modules, while once again the perspicacity of the developers of the standard deserved praise.

The fact is that the memory controller was located directly in the CompactFlash module, in much the same way as in hard drives. Thanks to this, the latest high-capacity cards could be installed in a relatively old camera. This flexibility has given the CompactFlash standard unrivaled longevity.

However, placing the controller on the map has its downsides. First, this increases the cost of the device. Secondly, as a result, manufacturers get "hands untied" and they label cards indicating "unformatted capacity" (for example, "64 MB"), although in reality 60 to 63 MB remain free for data storage.

After the spread of the USB interface, CompactFlash-USB data readers became popular. Moreover, CompactFlash modules appeared, which had a chipset that implemented the USB interface. These modules were equipped with a cable that had two connectors - one was intended for connecting to a computer's USB port, and the second, 50-pin, allowed you to connect a CompactFlash card directly to the cable and read data from it into a computer without any additional devices.

Perhaps, in the field of minicomputers, CompactFlash modules have become as widespread as in digital photographic equipment. Moreover, the reserves built into the interface (actually inherited from PCMCIA) made it possible to implement not only memory modules, but also modems and network cards within this format.

In general, the CompactFlash standard for the most part satisfies all modern requirements and is notable for its high popularity, good exchange rate and large reserves for increasing memory volumes.

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How digital cameras work

Most digital cameras have an LCD screen on which you can immediately view the resulting image. This is one of the main advantages of digital cameras. These photos can be viewed on a computer or sent by e-mail.

Digital cameras, in addition to shared memory, also support flash cards that store the pictures you take. You can transfer photos from the camera to a computer or other device either via flash cards (SmartMedia, CompactFlash and Memory Stick), SCSI, USB, FireWire, or via floppy disks, hard drive and CD and DVD discs.

CompactFlash Memory Card Digital photos tend to take up a lot of space. The most common formats are TIFF, unzipped, compressed JPEG (archived), and RAW. In this case, the data is stored in the form in which they were received from the photosensitive matrix. Therefore, the quality of RAW images is significantly higher than the quality of JPEG images, but they take up much more space. Nevertheless, most digital cameras use the high and medium quality JPEG format to store pictures.

Almost all digital cameras have special data compression programs that allow you to reduce the size of photos and free up some space for other pictures. There are two types of compression: compression based on repeating elements and compression based on "extra details". For example, if 30 percent of the photo is blue skies, this means that the photo will have too many repeating shades of blue. Special programs “compress” these repeated colors, so that the photo does not lose its brightness, and there is more free space on the camera. This method allows you to reduce the size of the image by almost 50 percent.

Compression based on "excess details" is a more complex process. As a rule, a digital camera captures more colors than the human eye perceives. Therefore, as a result of such compression, some “unnecessary details”, so to speak, are removed from the picture, due to which the weight of the photo is reduced. Summarizing:

To take a picture, the CCD camera performs the following operations:

First you need to point the camera at a certain object and set the optical zoom, i.e. zoom in or out on an object.
Then lightly press the button.
The camera automatically focuses on the subject.
The camera sets the aperture and shutter speed for optimal exposure.
Then you need to press the button again until it stops.
The camera exposes the CCD and when the light reaches the CCD, it charges each of the elements - pixels individually. This charging further corresponds to an electrical impulse, and thus we obtain in digital form data on the illumination of each of the pixels.
An analog-to-digital converter (ADC) measures the charge and creates a digital signal that represents the charge values ​​in each individual pixel.
The processor collects data from various pixels and creates a specific color range. On many digital cameras, you can immediately view the resulting image on the screen.
Some cameras compress the image automatically.
Information is stored on one of the types of storage devices, for example, on a flash card.

This FAQ was compiled by popular demand from the conference site participants. It provides answers to regularly asked questions about the technical side of photography. Choosing a camera is a topic for another discussion.

Terminology:

Problems:

Photo processing:

Technical questions:

TERMINOLOGY

Q: What is CFC?
A: It's short for Digital Camera. Modern CFCs can be divided into two main classes:

  1. Compact CFCs.
    In most cases, they have a fixed lens and, as a rule, a small matrix. Sighting is usually done using an LCD screen (TFT), sometimes - rotary. The viewfinder, if available, can be optical (as on film soap dishes) or electronic (a full functional analogue of the screen). DSCs of this class have limited capabilities, but they are cheap and relatively compact. Formally, some CTFs with big matrix and sighting on the screen, although in terms of cost, size and weight they are not inferior to the CPC of the next class.
  1. Mirrored DSCs (DSLR).
    They have the ability to use interchangeable lenses, which greatly expands their capabilities. They have large matrices, which affects the dimensions of the digital camera and lenses. Sighting is performed using an optical viewfinder, the image on which is fed from the lens using a folding mirror. The viewfinder also provides information about shooting settings, focus points, etc. The LCD screen is only used to set up the camera and view the photos you have taken. Currently, some SLR DSCs have the ability to view the screen, but this is associated with a large number of restrictions (b/w picture, manual focus only), which makes it impossible to actively use this mode. However, things may change in the future...

There are also non-SLR cameras with interchangeable lenses, such as the rangefinder Epson R-D1.

Q: What is EXIF?
A:
This is the name of the universal file header standard, which provides for the storage of the image itself, its reduced copy and text data in one file. Usually, EXIF ​​is understood as text information, which contains the date and time of shooting, a description of the shooting parameters, camera settings, and much more. The vast majority of image viewers allow you to read EXIF.

Q: What is “lag” (“shutter lag”)?
A:
In a broad sense, this is the time interval from pressing the shutter to actually taking a picture with the camera. It includes all the delays from pressing the shutter to taking the photo:

  1. Time to bring the lens into working position (there were cameras in which the lens went out at the time of shooting, then drove back);
  2. Time for autofocus;
  3. Exposure time;
  4. Time to remove the charge from the matrix (for compacts);
  5. Flash charge time (if required);
  6. Pre-flash time for flash metering;
  7. Time to raise the mirror (for DSLRs);
  8. Anti-red-eye pre-flash time;
  9. Time for other thoughts of the camera about the eternal.

The greatest lag is for old digital compacts with autofocus, the smallest - for SLR cameras and non-autofocus film "soap dishes".

With a lag of about a second or more, the camera subjectively feels like an “incredible brake”, suitable only for static scenes.
With a lag of up to half a second, in principle, you can already shoot moving objects, but there is no way to guarantee a snapshot.
With a lag of a quarter of a second or less, the lag ceases to interfere with most users.

In a narrow sense, the term "shutter lag" is commonly used by DSLR users and means the time from fully pressing the shutter (without autofocus) until the shutter curtains begin to move.

Q: What is "chromatic aberration" (CA)?
A:
XA is one of a number of image distortions caused by non-ideal optics. Chromatic aberrations are caused by the dispersion of light that occurs when it passes through a lens. This phenomenon is due to the fact that rays with different wavelengths are refracted at different angles. It manifests itself in the peripheral parts of the image field and is expressed in the appearance of a multi-colored "fringe" on contrasting objects (for example, on tree branches). It is most pronounced in cheap lenses and ultrazooms.

In addition to CA, the appearance of "fringe" is due to blooming - the flow of charge carriers from overexposed cells of the matrix to neighboring cells.

Q: What is distortion?
A:
Distortion is an optical distortion, which is expressed in the curvature of straight lines. Depending on whether straight lines become concave or convex, the distortion is called pincushion or barrel distortion. Zoom lenses tend to produce barrel distortion at "wide" (minimum "zoom") and pincushion distortion at "telephoto" (maximum "zoom").

Q: How is the light transmission of a lens determined, how can it be changed, and what does it affect?
A: The light transmittance of a lens is determined, on the one hand, by the area of ​​the active aperture of the lens (it changes with the help of the aperture), and on the other hand, by the focal length. The ratio of the focal length to the aperture diameter is called the f-number and is denoted by the letter K. The standard values ​​for K are: 1.0; 1.4; 2.0; 2.8; 4.0; 5.6; 8.0; 11, etc. As can be seen, they differ from each other by the root of 2 times, with each subsequent value of K providing a decrease in illumination by 2 times.

The reciprocal of the f-number is called the relative aperture of the lens and is denoted 1 TO. The maximum relative aperture value is indicated in the lens marking. So, the lens with the designation 28-135mm 1:3.5-5.6 has a maximum aperture ratio of 1:3.5 at a focal length of 28 mm and 1:5.6 at 135 mm.

Depending on the value of the f-number K, lenses are conventionally divided into the following groups:

  • superluminal (K ≤ 1.4);
  • fast aperture (1.4 medium aperture (2.8 low aperture (K > 5.6).

The higher the aperture (lower K number), the more light the lens lets through and the less often you need to use a flash or a tripod due to lack of light. Usually, with an increase in aperture ratio, other things being equal, the quality and, especially noticeably, the price of the lens increase. In professional zoom lenses, aperture, as a rule, does not change when zooming.

Strictly speaking, luminosity is the ratio of the illumination of the image created by the optical system to the brightness of the object. Since the aperture ratio is expressed as a decimal fraction less than 1 and therefore difficult to use in practice, it is customary to designate it as the maximum relative aperture (1: K), proportional to the square root of the aperture ratio.

In fact, in the jargon of photographers, the concepts of aperture ratio, relative aperture and minimum aperture number are mixed into one heap, so the expressions “aperture F / 2.8 (or f / 2.8, or just 2.8)” are quite common. But, in fact, it is correct to say “relative aperture 1:2.8”, “aperture diameter F:2.8”, “aperture number 2.8”, while the aperture ratio is 0.127.

Q: What is "dynamic range" (DD)?
A:
Dynamic range (or, more commonly for photographers, photographic latitude) is a value that characterizes the ability of a photosensitive material (photodetector) to reproduce with the same degree of contrast the differences in the brightness of the optical image areas of the subject. If we designate the minimum level of illumination at which the camera still “sees” details in the shadow as A, and the maximum level of illumination with details still visible in the light as B, then the A / B ratio will just be a numerical expression of the dynamic range. In photography, it is customary to express this value in stops (that is, in exposure changes by a factor of two). In addition, DD can also characterize the spread of brightness on the scene being filmed.

Simply put, the wider the DD of the camera, the wider the range of brightness it can transmit without loss in the same picture. If you shoot a very contrasting scene (having a large DD - landscape, architecture at noon, etc.) on a camera with a narrow DD, then in the photo the dark details (shadows) will turn out to be black, and the light details (highlights) will be white; there will be a loss of information (which, however, can be partially restored during RAW processing). DSC matrices are characterized by a very narrow DR compared to negative film, while DSCs are very fond of losing details in highlights - in particular, making the sky milky white in the picture, although, in fact, it is blue.

As a rule, the larger the geometric dimensions of the matrix in the DPC (not to be confused with the number of pixels!), the wider the DD. DD can be expanded by artificial methods - by “stretching” shadows / lights in the RAW converter, using a gradient filter, highlighting shadows with a flash, or combining pictures with different exposures in the editor.

Q: What is "white balance" (WB)?
A:
To explain this term, the concept of "color temperature of the light source" should be introduced. This is the temperature to which it is necessary to heat a completely black body so that it begins to emit light of a given shade. "Warm" light sources (such as a candle or incandescent lamp) have a low temperature, while "cold" ones (electronic flash, daylight) have a high temperature.

Adjusting the white balance (WB) allows you to adapt the color reproduction of the DPC to the color temperature of the light source. White balancing is to find such settings with which, when given lighting the white (actually grey) sheet of paper in the photograph will not have an extraneous color cast.

You can set up BB in different ways:

  1. Automatic (normal accuracy is achieved only in natural light and when shooting with flash);
  2. By choosing one of the preset settings in the camera (“incandescent lamp”, “fluorescent lamp”, “day”, “shadow”, “cloudy”, “flash”, etc.);
  3. Telling the camera what color to consider "white" (the so-called "manual WB");
  4. Specifying the temperature of the light source in Kelvin manually (this will require a special color temperature meter).

The complexity and accuracy of these methods increase from the first to the last, while the latter method is practically not found in the entry-level CTF.

All 4 ways to set the WB can be used when processing a picture taken in RAW (in this case, the WB set at the time of shooting becomes only one of the possible options). In this case, you will see how the colors change with different settings.

There are two things to keep in mind when setting up a WB.

First, under sunlight, the light in the shadows has a higher color temperature than in the highlights, and therefore the ideal white balance for the entire frame is unattainable in principle.

Second, color temperature describes only continuous spectrum sources. Since the spectrum of fluorescent lamps is not continuous, the passport color temperature of such lamps does not correspond to the true color temperature, but to the sensations of the eye, and it is very likely that under such conditions there is no way to achieve a color rendering from the matrix that matches the visual sensations.

Q: What is IPIG?
A:
This is short for "Depth of Field" (aka "depth of field", "depth of field"). In photography, the zone of sharpness is located both in front of the “in focus” subject and behind it. This more or less extended area of ​​high definition is the depth of field. Its length depends on the aperture opening (the wider, the less depth of field), the focal length (the larger, the less depth of field), the size of the camera matrix (the smaller the matrix with an equal viewing angle, the greater the depth of field, the more pixels with equal area, the less depth of field) and from the scene being shot (the greater the distance to the main object, the greater the depth of field around it).

Low DOF is useful for portraits, as it helps to separate the model from the background, as well as giving volume to faces and focusing on the subject. A large depth of field is needed when shooting landscapes, interiors, macro and architecture (so that everything is sharp). In reality, for compact CTFs, the depth of field varies from "large" to "very large" depending on the installed aperture. The formulas for calculating the depth of field can be found in the article on our website.

Q: What is "hyperfocal distance" and how is it determined?
A:
If the camera's lens is focused at the hyperfocal distance, then the field of sharpness begins at half the distance from the camera to the point at which the lens is focused, and ends at infinity. In other words, focusing on the hyperfocal distance allows you to get the maximum depth of field.

The hyperfocal distance depends on the size of the light detecting element, the focal length of the lens, and the aperture. To calculate it, you can use any of the online IPIG calculators, for example:

Hyperfocal focusing is often used in landscape photography and other situations where you need maximum depth of field or don't have time to focus on your subject accurately.

Many cheap cameras (like webcams, cell phones, $100 soapboxes, etc.) have lenses that are hard-focused at hyperfocal distance and have no focus mechanisms. Sometimes such lenses are called "focus-free".

Q: How to understand the designation of the matrix in inches (1/1.8, 1/2.5, etc.) and what does this parameter affect?
A:
The designation of the matrix characterizes the geometric size of the chip. Historically, the marking of matrices corresponds to the marking of vidicons in terms of outer diameter with the size of the light-sensitive area equal to the matrix. The designation does not allow one to accurately calculate the actual size of the matrix (but it makes it possible to compare matrices of different sizes with each other).

To denote large (larger than 4/3″) matrices, the so-called crop factor (Kf) is usually used. This is the ratio of the diagonal of a 24×36 mm film frame to the diagonal of a given matrix. Matrices with Kf>1 are often called "cropped" (as opposed to "full frame" matrices with Kf=1). By the way, EGF = Kf × FR.

One of the most important characteristics depending on the size of the matrix is ​​its noisiness. So, a DSC with an APS-C matrix (22 × 15 mm, Kf = 1.6) allows you to set ISO eight times higher than a device with a 1 / 2.7 ″ matrix (5.4 × 4.0 mm, Kf = 6.4) while maintaining approximately the same noise level. Note that the image noise also depends on the sharpening (in-camera sharpening) and noise reduction settings, so matrices of the same size on different cameras often make different noises.

The size of the matrix also affects the depth of field - the larger the matrix, the smaller the depth of field with an equal viewing angle and the same number of pixels. In addition, large matrices have a wider DD, more natural and more natural colors.

But for the quality that a large matrix provides, you have to pay - the size of the optics increases, and the price increases. Therefore, the more compact the device and the cheaper it is, the smaller the matrix is ​​​​installed in it.

Here are the most common sensor sizes compared to a 35mm film frame:

Q: What is focal length(FR) lens and what does it affect? What is equivalent focal length (EFF)?
A:
The focal length of a lens consisting of a single thin lens is the distance from the lens to the screen at which a parallel beam of light passing through the lens will converge to a point (or the image of an infinitely distant object will be sharp). The FR of a multi-lens lens coincides with the focal length of a single-lens lens that creates an image of the same scale as it. This definition does not apply to lenses with external dispersion and internal collective elements, referred to in jargon as "fisheye".

For practical purposes, it is much more important to remember that the angle of the camera's field of view depends on the ratio of the DF to the size of the matrix.

  • If the FR is approximately equal to the diagonal of the matrix, then such a FR is called "normal" and it is believed that in this case the angle of view (45 degrees) corresponds to the capabilities of the human eye.
  • If the FR is larger than the diagonal of the matrix, then such lenses are called “long-focus” or “telephoto lenses” - they provide a stronger approximation compared to “normal”, but the angle of view decreases.
  • If the FR is smaller than the diagonal of the matrix, then such lenses are called "short-focus" or "wide-angle" - they provide an expansion of the field of view compared to "normal", but at the same time the size of objects in the frame decreases.

For example, for a 15x22mm (APS-C) sensor, a 30mm lens is considered normal, for 24x36mm film it is considered wide-angle, and for a 5x7mm (1/1.8″) sensor it is considered telephoto.

Since the use of the ratio of the DF to the diagonal of the matrix is ​​not always convenient, the concept of equivalent focal length (EFD) is used to classify lens-matrix systems. It is conditionally accepted that the EGF of a given "lens-matrix" link is such a value of the focal length of the lens at which an image is obtained on a 35-mm film with the same angle of view as when using this link. EGF=Kf×FR.

So, if you have two cameras with matrices of 24x36 mm and 15x22 mm, as well as a zoom lens, then inserting it into a "full-frame" camera and setting the DF equal to the EGF for an APS-C sensor camera, you will be able to see in the viewfinder an image similar to that seen in the viewfinder of an APS-C sensor camera.

Let us give another example of the use of EGF. Suppose we have a DTF with a 7mm lens and a 1/1.8″ sensor. Kf of such a matrix is ​​approximately equal to 5. EGF=FR×Kf=35 mm. Thus, a 35 mm film camera with a FR=35 mm lens will give the same angle of view as a CPC with a 1/1.8 matrix and FR=7 mm.

Accordingly, based on the EGF value, we can classify lenses in the following way:

  • EGF 20 mm 45 mm 80 mm EGF > 130 mm - narrow angle lenses (usually just the term "telephoto" is used).

This figure will help you visually assess the field of view of lenses with different EGF and diagonal angles of view.

It is important to remember that the term "equivalent RF" is conditional and can be used only to bring the angles of view of cameras with different matrices and lenses to the same denominator, as well as to calculate the safe shutter speed when shooting handheld. EGF does not carry any technical meaning.

Q: What is exposure? What is "stop", "EV"?
A:
Exposure is a measure of the amount of light that hits the sensor during illumination (they say "exposure time"). It is equal to the product of the intensity of the light incident on the matrix and the time during which it is exposed to radiation. Illumination is controlled by the aperture value, and the time is controlled by the shutter speed (shutter speed).

The combination of shutter speed and aperture is called exposure. Imagine a glass that can be filled with water either in a thick stream (open aperture, small f-number) in a short time (short shutter speed) or in a thin stream (closed aperture, large f-number) in a long time (long exposure). In both cases, the total amount of water entering the glass will be the same (the same exposure), but the "expocouples" will be different. Thus, exposure pairs "F / 4.0 and 1/30 s.", "F / 2.8 and 1/60 s.", "F / 5.6 and 1/15 s." give the same exposure. The choice of exposure pair depends on the purpose of the photographer and the technique used.

For a simplified description of the illumination of an object, the logarithmic value "EV" (Exposure Value) is used. Illumination of 0 EV is achieved if a subject with such illumination requires an exposure of "F / 1.0 and 1 sec." and sensitivity ISO 100. This illumination value is numerically equal to 2.5 lux. A change in EV per unit is equivalent to a change in illumination by a factor of 2 (1 EV equals 5 lux, 2 EV equals 10 lux, -1 EV equals 1.25 lux, etc.).

Changing the aperture or shutter speed by n EV changes the exposure by 2n times. Changing the sensitivity of the sensor (or exposure compensation in the RAW converter) by n EV affects the final image in the same way as a similar change in shutter speed / aperture. For aperture numbers, a difference of 1 EV is a change in the root of 2 times (for example, 2.8 and 4.0), for shutter speeds and sensitivities - a change of 2 times (1/500 s and 1/1000 s, ISO 100 and ISO 200).

In photographers' jargon, changing exposure is often expressed in "stops" or "divisions". 1 stop of the difference is identically equal to 1 EV, that is, changing the aperture or shutter speed by 1 stop changes the amount of light entering the matrix by 2 times (the aperture value changes to the root of 2 times, and the shutter speed changes by 2 times). ISO change can also be measured in stops.

Q: How to check the digital camera when buying it?
A:

If this is your first digital camera:

  1. Make sure that the digital camera is turned on and that the picture is visible on the screen when turned on.
  2. Check the optics, screens and housing for stains and mechanical damage.
  3. Check the smoothness of movement of all engines, rings and buttons - so that there are no jams, squeaks, backlashes.
  4. Make sure the camera is taking pictures and the photos can be viewed on the screen. Make sure the built-in flash is working.
  5. With auto focus and when zooming, you should not hear anything other than the buzzing of motors and soft clicks. No crack.
  6. Check the correct operation of the lens shutters (it happens that they wedged).
  7. Make sure faces are in focus in photos and colors are not distorted. Use the vendor's computer.
  8. Don't forget to check the package contents (instructions, cables, discs, charger, etc.) and get a warranty card.

If you are more "advanced", additionally check on the photos on the computer:

  1. The presence / absence of various aberrations (distortions) like halos, tails from light sources, rainbows and other unpleasant things.
  2. Resolution uniformity across the frame field. To do this, take a picture of a newspaper (located strictly perpendicular to the optical axis) and compare the sharpness in the center and at the edges of the frame.
  3. Autofocus accuracy (front / back focus) for SLR DSCs. You can check by photographing at an angle of 45 degrees (file in pdf format also contains a detailed description of the entire process on English language) or regular ruler. In the most extreme case, a newspaper with text is also suitable.
  4. The presence / absence of broken and hot pixels.

It is recommended to buy photographic equipment in such stores, where you can check it before payment, and not after. If the store refuses to provide you with a camera or lens for a comprehensive check, turn around and go to another store.

It may not be possible to view pictures on a computer in a store - in this case, you can take pictures on your memory card and view them at home (after writing down the serial number of the DSC and asking the sellers to put it aside for you for a while).

Q: Dead and hot pixels, how to deal with them?
A:
Dead pixels look like white dots in the picture, they appear at all shutter speeds. These are defective, non-working sensor elements.

Hot pixels look like colored dots and appear at slow shutter speeds (the longer, the more likely they are).

The search for dead and hot pixels is carried out by taking a series of pictures with different shutter speeds (from 1/30 to 4 seconds) and with the lens closed from light. In this case, the ISO value should be minimal. It is best to view the resulting images on a computer.

Some RAW converters allow you to “subtract” dead pixels so that they won’t be noticeable in the final frames. To rewrite the dead pixel table (remap) stored by the camera, you can contact the service center. In addition, some DSCs allow the user to overwrite the dead pixel table on their own (automatically after pressing the "Reset" button, or by calling a special command from the menu).

Q: Should I buy an external flash or is the built-in one enough?
A:
An external flash is usually more powerful than your camera's built-in flash, so it will better illuminate the subject and increase the area illuminated. In addition, a powerful autofocus illuminator is usually built into an external flash, effective at a distance of up to 10 m (in complete darkness).

Often an external flash has a swiveling head, and if you point it at the ceiling, the lighting will be less harsh, more natural. In addition, since the external flash is far from the optical axis of the lens, the red-eye effect is reduced (and completely disappears when shooting with a reflector).

Flash output is characterized by a guide number (HF). It is numerically equal to the flash range (in meters) at ISO 100 (for older flashes at ISO 64) and f-number 1.0. To determine the actual range, it is necessary to divide the HF by the f-number. For ISO 50, the result must be further divided by 1.4, for ISO 200 - multiply by 1.4, for ISO 400 - multiply by 2, etc. The built-in flashes of compact DSCs have a guide number of about 7, for DSLRs - about 11, and for external flashes - 20-55.
Therefore, if with an aperture of F / 2.8 and ISO 100 the range of the built-in flash of a compact digital camera is about 2.5 m, then the external one will allow you to illuminate objects that are 20 m away!

You can read more about reflectors and diffusers in the article Flash Accessories. In addition, you can read about the device and features of external flashes.

Q: What are the types of memory cards (flash cards) and how do they differ?
A:

  1. Compact Flash (CF). One of the oldest memory card formats, which is being replaced by more compact formats in amateur digital photography. Nevertheless, in a number of indicators, it still surpasses all competitors.
    It is characterized by:
    (+) Most low price per unit volume.
    (+) Built-in memory controller - the volume of cards supported by a particular camera is limited only by the capabilities of the file system.
    (+) The largest amount of memory from the issued cards.
    (+) Good speed characteristics.
    (+) Possibility to use it in any laptop through a passive adapter "CF>PC Card" costing about $4.
    (–) Potential damage to the connector pins if the card is inserted carelessly.
    (–) Relatively large sizes.
    Currently, almost all memory modules are produced in the Type 1 form factor, which is supported by all devices designed to work with CF. There is also the Type 2 form factor, which creates peripheral devices (not designed to work with the DSC) and tiny IBM Microdrive hard drives (characterized by gluttony and fragility). Both types of cards (1 and 2) can be installed in the Type 2 slot.
  2. Secure Digital (SD). The modern standard for memory cards, currently pushing CF out of the market.
    They are characterized by:
    (+) Low cost per unit of volume (slightly more than that of CF).
    (+) Compact dimensions.
    (+) Mechanical write protection (as on 3.5″ floppy disks).
    (+) High performance.
    (–) Low prevalence in professional photography.
    (–) Relatively low maximum card size.
    A smaller version is Mini-SD.
  3. MultiMedia Card (MMC). This is the predecessor of SD, outwardly it differs in its thinner thickness, the absence of one contact and the write protection shutter. A device designed for SD usually allows you to work with MMC, but not vice versa. It is not recommended to use MMC instead of SD in digital cameras - due to the low speed of MMC, a decrease in the speed of burst shooting, as well as video "braking" is possible.
    They are characterized (compared to SD):
    (+) The price is slightly lower than that of SD.
    (–) Generally slower than SD.
    (–) The maximum size of modules guaranteed to work on any device is 64 MB (although both 256 and 512 MB are available).
    Reduced version - RS-MMC.
  4. Memory Stick (MS). The Sony standard, which, as always, decided to go "its own way." The result is a product that is inferior to SD in a number of ways.
    (+) Write protection shutter.
    (+) Good protection of contacts from damage.
    (–) Not compatible with anything other than Sony, LG, and some Minolta models.
    (–) Relatively large sizes (but smaller than CF).
    (–) Cards sold are smaller than SD cards.
    (–) High price (1.5 times more expensive than CF and SD).
    Reduced version - MS Duo.
  5. xD Picture Card (xD). Fujifilm and Olympus standard. In theory - very promising, in practice - expensive and rare.
    (+) Small dimensions.
    (–) Incompatible with anything other than Olympus and Fujifilm.
    (-) Low speed.
    (–) High price (at MS level).
    (–) Cards sold are smaller than SD cards.
  6. SmartMedia (SM). Very old format, precursor to xD. Features are even worse than xD, plus large size and a maximum capacity of only 128 MB.

If you look objectively, the best formats today are CF and SD, they are also the most common. But, nevertheless, when choosing a DSC, the type of memory card should be of secondary importance, unless, of course, you have a stack of cards for several GB and / or a PDA with one or another slot.

Q: Which company's memory cards are better?
A:
There is no single answer to this question and there cannot be. Now there are a number of manufacturers of memory cards on the market, producing products of approximately the same level. These are SanDisk, Transcend, Pretec, Apacer and Kingston. The choice between these manufacturers is a matter of your taste.

It is worth noting that in the case of CF, SD and MMC cards, it does not make sense to buy "native" memory from the manufacturer of your digital camera. Such cards are much more expensive, but they are products of the above companies with different inscriptions on the sticker.

Q: Do I need to buy the fastest memory card?
A:
Doesn't make much sense unless you're going to be shooting long bursts of RAW on a DSLR on a regular basis. In compact DSCs, the difference between "normal" and "high-speed" memory cards can be noticed only if you specifically record the recording time with a stopwatch (and even then it's not a fact that the DSC will be able to realize the full potential of the card). If you use a card reader to transfer photos to a computer, a “fast” card will provide a noticeable acceleration in transferring pictures. In other cases, it will be enough to have cards with a speed of 40x or more.

Of course, very old memory cards will show poor speed characteristics, but to find such cards on sale, you need to try very hard.

Q: What is a RAW file and do I need it in my digital camera?
A:

Easy level.
RAW is a "digital negative" file. It requires mandatory processing in the appropriate programs on the computer. Compared to JPEG from the camera, it allows you to set WB (white balance) during image processing, and not just during shooting, which helps in cases of shooting under difficult / mixed lighting. It also makes it possible to correct the exposure (brightness) within ±2 EV during processing in the converter without significant artifacts (not counting the increase in noise corresponding to the increase in ISO in the camera). With more complex processing, other advantages become noticeable.

Advanced level.
RAW (raw - raw, unprocessed) - a file containing non-interpolated data read from the matrix sensors. The bit width of the data corresponds to the bit width of the ADC (usually 12 bits, but 10 and 14 bits are also found). The volume of an uncompressed RAW file is calculated from the number of sensors on the matrix (megapixels) multiplied by the ADC bit depth (10-14 bits depending on the model) + JPEG preview, which is also packed into a RAW file. For some cameras, a *.thm file containing EXIF ​​data (including a small preview) is written to the same folder with RAW.

Many devices (mainly mirrors) use RAW file compression to significantly reduce the space occupied and speed up recording. As a rule, this is lossless compression, but there is also a slight lossy compression (compressed NEF files in some Nikon cameras).
Typically, a RAW file has an extension that matches the camera manufacturer: CRW or CR2 for Canon, MRW for Konica Minolta, NEF for Nikon, PEF for Pentax, RAF for Fujifilm, ORF for Olympus, etc.

Advantages of RAW files over in-camera JPEGs and TIFFs:

  1. Possibility to install WB retroactively during conversion, which greatly simplifies and speeds up shooting in difficult lighting conditions.
  2. Possibility of introducing exposure compensation during conversion. Usually within 0.7-1 EV this is not accompanied by side effects in the form of the appearance of posterization (when corrected up) or unwanted colors (when corrected down and the presence of overexposure in the image). Correction in the range of 1-2 EV can give these side effects, but they are less pronounced than similar ones when correcting an already converted file. It should be noted that upward exposure compensation is always accompanied by an increase in noise. So, a frame taken at ISO 100 and "stretched" by 1 stop in the converter differs little in noise from a picture taken at ISO 200.
  3. Possibility of performing better interpolation. The interpolation process in the camera is limited by a rigid time frame and is limited by the small computing resources of the in-camera processor. Interpolation on a powerful computer using complex algorithms allows for higher detail, and also allows you to painlessly save the result in a lossless or uncompressed format (saving as TIFF in the camera, as a rule, takes a long time), which is favorable for further processing in a graphics editor.
  4. The ability to manipulate DD, since instead of 8 bits per RGB channel of an in-camera JPEG or TIFF, after interpolation from RAW, we have 10-14 (most often 12) bits per channel, which allows us to shift the range of the final image towards highlights or shadows.
  5. The ability to use noise reduction and sharpening algorithms at your discretion both at the conversion stage and after it instead of simplified (usually) in-camera algorithms.
  6. Possibility to use at the stage of conversion curves of any complexity, including those prepared by oneself, instead of a rather simple curve used when converting in a camera, the shape of which is controlled by a few simple values.

To the question of what is better to use - JPEG or RAW. If you fundamentally do not process images on a computer, then perhaps JPEG will be preferable for you. In other cases - RAW, as it provides an order of magnitude more processing options. If you don't have time to convert photos individually, you can do it in batch mode; at the same time, no user intervention is required, and the photos are similar to those that the camera produces in JPEG. In this case, RAWs are usually not deleted and can be processed manually later.

It should be borne in mind that compact cameras usually use uncompressed RAW, which, combined with a small buffer size, makes it impossible to shoot quickly in RAW (one frame is written to the card for several seconds). At the same time, even the cheapest DSLRs allow you to shoot RAW in bursts, while the rate of fire is more than sufficient for most hobbyists. (That is, during normal shooting, the difference in speed between RAW and JPEG is imperceptible.)

If your camera allows you to save images in TIFF, do not use this format instead of JPEG and, even more so, RAW. Because when recording to TIFF, the file size and recording time increase many times, and there is simply no difference between TIFF and JPEG of maximum quality in the vast majority of pictures.

Q: Why do we need filters?
A:
There are five main purposes of applying filters:

  • change in the spectral composition of light;
  • attenuation of the light flux for shooting with slow shutter speeds and an open aperture;
  • analysis of the degree of polarization;
  • receiving special effects;
  • use not for its intended purpose, to protect the lens from mechanical damage (scratches, dust, splashes).

Filters can be divided into 4 groups.

  1. absorbing or transmitting light in a certain range of wavelengths. These include: UV, Skylight, Cyan, Yellow-Green, Yellow, Orange, Red, IR, Zone and Conversion filters.
    In digital devices, filters that cut off UV and IR radiation are already installed, so installing additional filters will not have a serious effect, unless the filter built into the device can be removed. Color filters are also already installed and their effect, usually important only in B/W photography, can be obtained in a graphics editor by converting a color image to monochrome.
  2. Neutral filters. They are also built into some devices and are used to limit the luminous flux instead of a diaphragm or in conjunction with it. These filters do not change the spectral composition of the light passing through them. Can be useful for long exposures (for example, when shooting water) and for shooting at wide open aperture in conditions where the fastest shutter speed cannot limit the light output to an acceptable value (for example, shooting a portrait outdoors on a sunny day). Gradient filters are a special case of such filters. They allow you to reduce the dynamic range of the scene already when shooting, so that both lights and shadows work out well. Such a filter can be useful in scenes such as "above - a light sky, below - a dark earth." Gradient filters with central symmetry are used to compensate for vignetting in some lenses.
  3. Polarizing filters. Such a filter even at the shooting stage makes it possible to cut off polarized light, which allows you to remove glare from non-metallic surfaces (water, glass) and make the color of a cloudless sky more “deep” - while the picture becomes more contrast, clouds are better visible in the sky. It is impossible to simulate the action of such a filter on a computer.
  4. « Spectacular filters." In fact, these are not filters, but optical nozzles, consisting of prisms, diffraction gratings and scattering elements. They can be used for both scientific photography and artistic effects. Their artistic effect can be simulated on a computer. However, computer processing is unable to reconstruct the true spectrum of the unknown source.

Some filters of the first group (UV and Skylight) can be worn permanently screwed to the lens to protect the optics from mechanical damage, as well as dust, splashes, fingerprints. These two types of filters have almost no effect on the final image (except that Skylight 1A brings a weak pink tint, and 1B a stronger one). Specialized "protective" filters are also sold (in terms of their effect on the final image, they are similar to UV filters).

You can read more about light filters in a series of articles.
Discussion of different manufacturers of light filters: You can read about shooting in the mountains using gradient and polarizing filters, as well as hoods in this article on our website.

Q: What equipment do you need for underwater photography with a digital camera?
A:
For underwater shooting with a digital camera, you need a special waterproof box. If you intend to shoot underwater, make sure that such boxes are sold for your camera before purchasing a CPC. In addition, keep in mind that the price of an underwater box can be even higher than the cost of the camera itself. Some cameras are waterproof on their own. Also produced and special illuminators for underwater photography.

It should be remembered that "waterproof" is a loose concept. Therefore, before buying a CFC or a water-proof box, you should pay special attention to the conditions under which security is guaranteed. Usually, the maximum time spent under water (for example, 30 minutes) and the maximum depth of immersion (for example, 1 m) are regulated. If these requirements are not observed, water may enter the housing with the subsequent failure of the CFC.

Q: Do I, an amateur, need a tripod, and which one?
A:
A tripod is used when shooting in low light conditions, on telephoto lenses, as well as for photographing panoramas and macro. In addition, using a tripod, even under normal conditions, allows the photographer to compose the shot more accurately. The combination of tripod and self-timer allows the photographer to put himself in the frame. Decide if you need it or not.

It makes sense for an amateur to take a tripod designed for cameras weighing up to 2.5 kg. When unfolded, such a tripod has a height of approximately 150 cm (usually, the higher the tripod, the more convenient it is). When folded - about 60 cm. The weight can be different - from 0.7 to 2 kg. Requires vertical shooting capability and quick attachment to the camera (quick release plate with tripod screw). Pay attention to the presence of a cover in the kit - this is a very useful thing. For panoramic shooting a bubble level is required. For macro - reversible central shaft. It is advisable not to take tripods with a long (25-30 cm) handle - they are designed for video cameras, and this handle will get in the way when shooting.
These models cost $20. The optimum is about $40-60. The cheapest tripods tend to be quite flimsy and unstable, while the expensive ones are usually stiffer and more functional.

If the “adult” tripod is too bulky for you, then you can pay attention to the pocket version. Such tripods when folded have a length of about 10 cm and normally fit in the back pocket of trousers. In the unfolded state, the length reaches about 30 cm. In some cases, such a tripod is very convenient, but for shooting it has to be placed on some object. In addition, they are designed for cameras weighing no more than 0.5 kg. The cost is from $3 to $25. Expensive models have fixation of the legs in the unfolded position and, in general, are more high quality assemblies.

You can read more about the design features of tripods in this article on our website.

SHOOTING TECHNIQUE AND TIPS

Q: How to save photos while traveling when there is no computer nearby?
A:
There are two approaches:

If a trip is planned to a civilized place, then the easiest way is to contact a photo lab and copy the data to CDs. In Europe, copying data to CD usually costs between €3 and €5. In resort towns it reaches up to €10. In Russia - usually from €1 to €3. In this case, 512 MB memory cards are very convenient (one card - one disk).

If you plan to travel to places that do not have such a service, then there are devices that allow you to copy data from memory cards to the built-in hard drive (a hybrid of a card reader and a hard drive in a basket with a battery). There are also devices that allow you to copy data directly from the camera via USB to the built-in hard drive.

Q: Why does my camera take so long to fire (the cat ran away, the child turned away...)?
A:
If you have a compact camera, then a large lag is quite normal. You can reduce it in different ways:

  • Focus in advance on the subject or on the place where it should appear (use the half-press of the shutter - see the instructions for the camera).
  • Use manual focus mode and set the lens to hyperfocal distance (if possible).
  • Turn off the screen, use the optical viewfinder (not electronic!).
  • Use the "Shooting children and pets" mode (some DSCs have it), in which the lens is set to hyperfocal automatically.
  • Disable red-eye reduction (especially if using flash).
  • Disable autofocus assist light.
  • Do not use depleted power sources that slow flash charging.

Q: Can I shoot with a digital camera in the cold?
A:
In the cold, two aggressive factors lie in wait for a digital camera - the actual low temperature and moisture / condensation.

Batteries are afraid of low temperatures, especially Li-Ion - at temperatures below 0 degrees, their capacity drops sharply (Ni-MH tolerate low temperatures better). Therefore, in winter, you should move the batteries separately from the camera in a warm place and install them in the CPC only for the time of shooting. A Li-Ion battery that has sat down in the cold can be warmed up and you can take a few more shots. In any case, when shooting in the cold, it is advisable to have spare batteries.
In fact, temperatures above the order of -15 degrees are not very terrible for the camera - in the worst case, the grease in the lens will thicken (if this happens, then you cannot use the camera). At low temperatures, there is also a “braking” of the LCD screen, but this should not be feared - at positive temperatures everything returns to normal.

By the way, the camera heats up during operation. A warm battery lasts longer than a cold one. Therefore, if the camera is already taken out of a warm place and started shooting, do not turn it off for short breaks in work. And, if possible, turn off the display and use the optical viewfinder - the display consumes a fairly large current.

High humidity and condensation (have you ever entered a warm room with glasses from a frost?) Harmfully affect the optics and electronics of the camera. Therefore, it is necessary to carry the CFA not under clothing (it is humid there), but in an ordinary photo bag. After entering a warm room, do not open the bag with the camera for several tens of minutes (ideally, a couple of hours). Otherwise, when the camera heats up quickly, condensation will form on the inner and outer surfaces, which will be very difficult to remove.

These recommendations are verified by the experience of many photographers. But we consider it our duty to warn that the company's warranty does not cover damage caused by shooting in conditions not recommended by the manufacturer.

Q: Can I shoot "on automatic" or do I need to use manual settings?
A:
If you are satisfied with the quality of pictures taken in automatic mode, then why not? Another thing is that in creative modes (Program, Shutter Priority, Aperture and Full Manual) you have the opportunity to use the full potential of your equipment. True, in the absence of shooting experience and theoretical knowledge, the chance to spoil the picture also increases. A reasonable compromise seems to be using presets (portrait, landscape, etc.) or program mode, especially if it has the ability to “shift” the program (that is, change the combination of shutter speed and aperture).

Q: In the camera menu there is an item "image compression". What value to put?
Q: How to save space on the memory card as efficiently as possible?
A:
If you need to take a lot of pictures, and there is no way to buy additional memory, then obviously you will have to save money. The best way in terms of quality - leave the maximum resolution in the JPEG parameters, and reduce the JPEG quality by one step from the maximum. That is, if (for example) "poor", "normal", "good" and "excellent" are available in the JPEG quality settings, then "good" should be used. If compression is configured instead of JPEG quality, then it should be remembered that the maximum compression corresponds to the worst quality and vice versa.

Thus, the number of photos that can fit on a memory card will increase by about 2 times compared to maximum quality JPEG, while the visual quality will practically not suffer. At the same time, it should be noted that pictures taken in the "saving mode" are difficult to process in the editor - compression artifacts begin to come out. Remember that in almost any situation, the maximum quality of JPEG (or RAW in general) is preferable, and memory cards are now very inexpensive.

Using low resolution and high compression is not recommended, except, perhaps, when you need to quickly put the picture on the Internet and you do not have the time or opportunity to process it in the editor.

Q: Why are pictures taken in artificial light with unnatural colors and noise?
A:
The distortion of colors in the picture occurs because the white balance was set incorrectly (machine error or you forgot to remove the “street” preset). Set the preset corresponding to the type of lighting, or use the manual setting of the WB. Shooting in RAW allows you not to think about setting the WB in the camera at all.

Noise appears, as a rule, due to the fact that the brightness of the lamps is insufficient and the camera's automation sets the maximum sensitivity (ISO), and this leads to noise. There are two recipes for the fight - “add” light or manually set the minimum ISO value. In the latter case, most likely, you will have to use a tripod, since lowering the ISO will increase the shutter speed and handheld shooting can lead to blurring of the frame.

Q: What's the best way to shoot in the dark?
A:

Shooting without a tripod.
If the distance to the subject is less than 3-5 meters, you can use the built-in DSC flash and auto exposure, but be prepared for the background of the photo to come out black. That is, this method is not suitable for shooting people against the backdrop of the urban landscape - one can only guess what is behind the person being photographed.

If you are shooting a night landscape (or any other scene with a long distance to the subject), the flash should be forced off. Otherwise, the automation will “think” that the object is not far away and a flash is enough to illuminate it (which, as you remember, has a range of several meters). The result is a completely black photograph. Disabling the flash will give a better result (in a pinch, the same).

Modern compact DSCs are poorly suited for night photography without using a flash and a tripod. Raising the ISO sensitivity above 100-200 (for DSLRs - 400-800, respectively) is highly discouraged - noise will creep in. "Night" shooting modes will give some effect only if you have a tripod or other solid support. The luminosity of the optics is also not infinite and it is usually not enough for night shooting. The image stabilizer, although useful, is also not a panacea - it ensures handheld shooting at shutter speeds of only 1/15-1/5 s. (at a wide angle), which, as a rule, is still lacking. Hence the conclusion - to obtain high-quality night photographs, you need long exposures and a solid support for the camera (such as a tripod).

Shooting from a tripod.
Many cameras have a so-called "night" mode, which is optimized for night shooting and allows you to use slow shutter speeds. It should be noted that to shoot "a person in the background ..." you should use the night mode with forced flash (fill) on, while the person being photographed should not move during the entire exposure time (that is, several seconds). In such a situation (if possible), you should indicate to the camera the shortest of the “night” shutter speeds - the longer, the less likely it is that the person being photographed will turn out to be clear.

When photographing a “clean landscape”, on the contrary, it makes sense to use slower shutter speeds (respectively, a more closed aperture) to increase the depth of field, the appearance of colored traces behind cars and “rays of light” from lamps. I note that when shooting from a tripod, you should use the minimum ISO value - with slow shutter speeds, compact cameras noticeably increase noise.

You can deduce the following pattern: the more expensive the CFC, the higher the quality of the matrix in it, and the better the night photos are. You can read more about how various cameras shoot at night at.

A separate problem that occurs when shooting at night is the unstable operation of autofocus in the dark. If the camera refuses to focus even when the AF illuminator is on, you can try focus-lock mode. To do this, you need to aim (half-pressing the shutter release) at a brightly lit object located at the right distance; frame without pressing the shutter to the end, and only then press the button. If you have a manual focus mode, you can specify the distance to the subject on the scale (if it exists, of course). In any case, if the camera is having difficulty focusing, you should close the aperture (respectively, increasing the shutter speed) to increase the depth of field - this measure will smooth out the consequences of incorrect focusing.

Q: What are the features of photography in the mountains?
A:

Q: What is the best way to shoot at sea / in bright sun?
A:

  • Photographers say: "Light is never too much." But in high light, compact cameras sometimes lack the shutter speed range, and the automation decides to close the aperture to a minimum. And this is fraught with a loss of sharpness due to diffraction (in modern compact DPCs, the maximum resolution is achieved at apertures of the order of 4-5.6). Therefore, it makes sense to use neutral density filters that reduce the light output.
  • In bright light, the visibility of the image on the LCD screen tends to zero (several backlight LEDs cannot be compared in brightness with the sun). Therefore, you will have to use the viewfinder, if you have one, of course :-).
  • When shooting, be sure to control the position of the horizon line - it must be strictly parallel to one of the sides of the viewfinder frame.
  • Beach photos are always characterized by the presence of very large contrasts of illumination. In this case, details in the shadows and / or highlights are lost in the photographs. To avoid this, you should use reflectors (at least white towels) aimed at the shaded side of the scene or the flash. Special attention this problem should be paid attention to when shooting portraits - faces are very often in shadow, which makes such photos the first candidates for removal.
  • It is recommended to use filters (UV, protective or Skylight) to protect the optics from salt spray. Be careful not to get the CFC into the water - with a very high probability this means the death of the device. (Often, users leave the camera bag near the water's edge, and then find it flooded. With all the consequences...) Do not leave the camera bag in the sun for a long time, and also in the car.
  • It is not recommended to take pictures during the midday hours. At this time, short shadows lead to the loss of a sense of the “volume” of the scene, and the brightness difference approaches the maximum. You should be especially careful when shooting portraits - overhead lighting creates unaesthetic-looking shadows under the eyes.

Q: What are the basic rules for shooting a portrait?
A:
For a detailed answer to this question, a large article or even a whole book is needed. Here we will try to describe only the main technical nuances that you should remember when shooting a portrait.

  • The shooting distance should be large enough, at least 1.5-3 meters, otherwise a strongly accentuated perspective effect appears and facial features are distorted.
  • When shooting a portrait, the aperture is usually opened to reduce depth of field. In this case, the facial features of the model acquire volume, and the background is blurred. The purpose of blurring the background is also the use of long-focus lenses (“portrait” lenses are considered equivalent focal lengths from 80 mm). When opening the diaphragm, you should estimate the size of the depth of field and make sure that important plot elements get into it.
  • It is not recommended to use sensitivity higher than ISO 100 for compact DSCs and ISO 400 for DSLRs. When shooting with flash, it is recommended to set the lowest possible ISO.
  • If your DSC supports the installation external flash with a swivel "head" - use this. An external flash in combination with a reflector or softbox allows you to improve the quality of a portrait by an order of magnitude compared to the built-in one.
  • You need to photograph a person from the height of his growth, especially for children. Otherwise - a strong distortion of the proportions of the face and torso.
  • When shooting against the light (backlit), always use the flash. Otherwise, the photo will either have a dark silhouette or an overexposed background.
  • When shooting indoors with a built-in flash, you need to make sure that the background is far from the person being portrayed - otherwise there will be a sharp shadow on the background. In addition, the shooting point should be chosen so that there are no unwanted objects behind the person being portrayed (a classic mistake - a tree or a lamppost “grows” out of a person’s head).

Q: What is a histogram and how to use it?
A:
A brightness histogram is a graph that shows what levels of brightness are present in an image. The range of brightness levels is represented as a sequence of vertical lines, from left to right, from darkest to lightest. The height of each line shows the relative number of pixels of the corresponding brightness.

When viewing a photograph you have taken, one glance at the histogram lets you know how well the camera's exposure meter worked. (This is especially useful when shooting in the dark or in bright light, when the brightness of the image on the screen does not give an idea of ​​the brightness of the photo itself.) If the histogram shows underexposure or overexposure, then the camera should activate the exposure compensation mechanism to correct the situation.

Let's demonstrate the principle of working with a histogram using specific examples:


Normal exposure. Shadows and highlights are well done. The strip corresponding to black color "belongs" to the tree trunk.


Overexposure. The picture is too bright - details in the highlights are lost. Negative exposure compensation required (approximately minus 2/3-4/3 EV).

Underexposure. The picture is too dark - details in the shadows are lost. Positive exposure compensation required (approximately plus 2/3-4/3 EV).

The dynamic range of the image is too narrow. This happens when shooting through glass, as well as when exposed to sunlight when the sun is close to the edge of the frame.
Remove glass :-); use a hood (or any improvised item as a visor).


The dynamic range of the picture is too wide - the bottom of the frame is too dark and the top is too light.
Do not shoot in cloudy weather (when the sky is already white) and against the sun. Use the flash to "light up" the shadows. Shoot in RAW and/or make negative exposure compensation for the subsequent "pulling" of shadows. Put on a gradient filter. Take several shots with different exposures and combine them in a photo editor.

For more information about using the histogram during the shooting process, see the article.

PRINTING PHOTOS

Q: What is the size of the photo in megapixels for printing 10x15 cm?
A:
The human eye is able to distinguish details about 1 arc minute in size, which is about 1/3500 of the viewing distance. With a best vision distance of 25-30 cm, we get an "eye resolution" of 12 dots per millimeter, or 300 dots per inch. The distance between the images of points on the retina will then be 0.005 mm, which is equal to the diameter of the cone in the macula. It follows that in order for the result on paper to be optimal from the point of view of the human eye, a 10x15 cm print must have a resolution of 300 dpi. At higher resolutions, you will need a magnifying glass to see the details.

Thus, to print 10x15 cm (that's about 4x6 inches), you need a matrix resolution of at least (4.5x300)x(6x300)=2.43 MP (taking into account the fact that compact DSC matrices are usually have a 4:3 aspect ratio and the photo will have to be cropped). It is worth considering that for large-format wall-to-wall printing, the minimum resolution requirements are reduced as the viewing distance increases.

You can read about the features of printing B/W photos in the article on our website.

Q: How can I calibrate monitor colors to match minilab/printer print?
A:
Strictly speaking, it is almost impossible to get a complete analog of the print on the monitor. For the colors differ depending on the color temperature of the monitor, the light source in the room, and the overall impression is still different due to the fact that the color monitor shows “through”, and the print shows “reflective”. Therefore, you need to be prepared for the fact that the print result may differ from what you see on the monitor.

The first step is to calibrate your monitor using the Adobe Gamma program according to the method described in the article "". Next - you should search the Internet for a color profile for a printer / minilab. Be aware of the type of paper and ink you are using.

  • If you use completely original consumables, then the necessary profiles are already built into the printer driver.
  • For a combination of original ink and non-original paper, you can search for profiles on the paper manufacturer's website.
  • Serious minilabs usually have their own profiles and provide them to their clients.
  • The maximum level of quality is provided by hardware calibration of the printer using a spectrophotometer - such services are provided by a number of companies and individuals. This method is also used in the case of using completely non-original consumables.

If you couldn’t find the minilab profile (and you often have to print in such minilabs), then it makes sense to “compress” your pictures into the sRGB color space before printing. In Photoshop CS2: "Edit > Convert to Profile".

If the sRGB profile is indicated in the Source Space, then no conversion is needed, otherwise, select the sRGB profile in the Destination Space list. When converting, color substitution occurs, the color substitution method can be selected by changing the Conversion Options, and achieve the desired result.

A more precise calibration is also possible with a special tool. Read more about this in an article on our website.

Q: How to prepare photos for printing in minilab?
A:
To begin with, specify what requirements the minilab imposes on photographs. The range of requirements can be very wide - from "carry everything as it is" to certain values ​​​​of size, dpi and format.

In any case, it is advisable to crop the image yourself. This means that if you are submitting a 4:3 aspect ratio photo for 10x15 printing, for example, you will need to crop the top and bottom of the image. It is convenient to do this in Photoshop by specifying the required dimensions in the Crop Tool settings.

As a rule, minilabs do not accept for printing pictures that are not saved in JPEG or TIFF (8 bit, uncompressed), and also have several layers. Using TIFF for printing in a minilab is impractical - a lot of time is spent on such photographs, and the difference with JPEG is not visible.

Concerning the correspondence of the colors of the picture on the monitor and on the print - see the question.

Q: What is the best program to print photos on a photo printer?
A:
Adobe Photoshop provides very good results - it allows you to connect profiles, crop frames, compose several photos on one sheet. If there are no special requirements for the program's capabilities, you can use the software that comes with the printer, or the print function from some image viewers.

PROBLEMS

Q: How to recover deleted/missing photos from a memory card?
A:
If after the “disappearance” of photos from the memory card you did not write anything to it, then the probability of successful recovery is quite high. Usually they use a card reader (or the DSC itself, if it can be used as an external drive) and specialized programs (both paid and free), for example, PhotoResque, Digital Image Recovery, PC Inspector File Recovery.

Q: How do I clean the lens and display of my digital camera?
A:
Before cleaning the optics, dust and the smallest grains of sand should be brushed off with a soft brush or a stream of dry air. After that, you can use special kits for cleaning optics, sold in photo stores. They include a non-marking grease remover and lint-free wipes. In field conditions, the Lenspen pencil helps a lot, but there are complaints about the work of this tool (this is dry, not wet cleaning). The use of monitor cleaners on optics is strongly discouraged.

DSC screens can be cleaned with almost anything you use to clean your glasses. :-) Because the screen coating is designed for harsh operating conditions and in any case gets scratches and scuffs over time. Of course, the use of special tools is preferable.

Q: How to clean the matrix of a digital SLR from dust that gets in when changing lenses?
A:
The safest option is to clean the matrix in the service. But this comes at a cost of time and money.

Self-cleaning of the matrix is ​​​​carried out in the appropriate operating mode of the DPC (read the instructions), when activated, the mirror rises and the shutter opens. To blow off dust, rubber pears from optics cleaning kits and vacuum cleaners are used. It should be remembered that the CFC matrix is ​​a very “delicate” and expensive device, so any mechanical contacts with it are strongly discouraged. Also, you should not use compressed air canisters to blow off dust, as they "spit" condensate. Please note that damage to the sensor during self-cleaning is not covered by the warranty.

In fairness, it should be noted that in 90% of photographs, traces of dust are hardly noticeable and it is often easier to “remove” them in an image editor than fiddling with cleaning the sensor (and not the fact that you will clean it and not cause more dust).

The process of cleaning the matrix is ​​described in the article on our website.

Q: How to protect the camera display from scratches and fingerprints?
A:
Computer stores sell screen protectors for PDA screens. It costs from €3 to €50 for a 3.5″ sheet. It is necessary to cut a segment of the desired shape from this blank and stick it. This film was originally designed for harsh environments (constant touch with fingers, pen, etc.). However, after sticking the film, the brightness and image quality on the screen may deteriorate. However, if necessary, the film can be removed from the screen without leaving marks (expensive options allow multiple use).

This film must not be stuck on the lens - use filters to protect it!

Q: What should I do if the CFC gets wet (was dropped into water)?
A:
If the chamber gets wet, hydrolysis of the conductors on the printed circuit board is possible. In this case, the repair will result in an amount comparable to the cost of a new device, and the reliability after the repair will leave much to be desired. To prevent hydrolysis, it is necessary to remove all power sources as soon as possible after CPA enters the water.

If hydrolysis has not occurred, then there remains a meager chance to bring the camera back to life (at least in order to make it to the point of buying a new one) - open all possible compartments and dry it. In principle, disassembling the device and rubbing it with alcohol (or even completely bathing the device in it) can help. But do not build illusions - after the device gets into water (especially salty!) The probability of "death" is extremely high. Even if you were able to "revive" the CFC, it can still fail at any time and it is better to get rid of such an apparatus.

Q: What causes the effect of "red eye" (RH) and how to deal with it?
A:
This effect occurs when the light from the flash reflects off the vascularized retina and enters the lens. The effect of "red-eye" is more pronounced when shooting in low light conditions, when the pupils are dilated, and directly depends on the distance between the flash and the optical axis of the lens. V compact cameras this distance is minimal and therefore almost all indoor shots suffer from the CG effect.

Most DPCs are equipped with a point light source that causes pupillary constriction (this can be done using special treatment flash operation) and slightly reduces red-eye.

How to fight:

  1. Move the flash away from the optical axis of the lens. So, installing an external flash can significantly reduce the CG effect, and using a softbox or reflector solves this problem completely.
  2. Use spotlights or natural light instead of flash. This may require an increase in sensitivity, resulting in increased noise.
  3. For obvious reasons, the first two methods are not applicable to entry-level compact DSCs. Owners of such devices can only recommend computer retouching of images. Many image viewers and editors allow you to remove red eyes automatically.

Q: Why do some photos come out blurry and how can I avoid this?
A:
Blurry photos can occur for one of the following reasons:

  • The movement of the camera at the moment of shooting.
    Fighting methods:
    1. Set the shutter speed in seconds no longer than 1 / EGF. So, with an EGF of 100 mm, it should be removed from the hands at a shutter speed of no longer than 1/100 sec. If there is not enough light for this, then you can use the flash, open the aperture, or increase the ISO sensitivity (with increased noise).
    2. Use a tripod, monopod or other support.
    3. Use the image stabilization system (if available). It, like a monopod, lengthens the “safe” shutter speed by 4-8 times.
  • The movement of the subject being photographed at the moment of shooting.
    Fighting methods:
    1. Shorten your shutter speed to values ​​that allow you to practically “freeze” the movement.
    2. “Follow” a moving object with a camera (panning shooting). Requires some experience. Naturally, motionless objects will be blurred. But this, as a rule, does not worsen the picture, but on the contrary, it adds dynamism.
      Using a tripod, monopod or image stabilization system will not save moving objects from blurring, since the shutter speed does not change in this case.
  • Wrong focus.
    1. Make sure that the focus point is always on the subject, which should be as sharp as possible. It's best to manually set the focus point before each shot rather than relying on the automatics. If it is not possible to set the point manually, it is advisable to use the center point and shoot with focus lock.
    2. If you have to shoot with manual focus (for example, in the dark), close the aperture to increase the depth of field.
    3. Always check if the camera was actually able to focus.
  • Insufficient depth of field.
    Remember that when shooting multi-layered scenes, the depth of field may not be enough, and some objects will turn out blurry. Therefore, when shooting on a DTF with a large matrix, you should always estimate the depth of field for a given scene and, if necessary, close the aperture.
  • Inappropriate aperture setting.
    Almost all lenses more or less degrade the picture at the maximum aperture. So, a lens with an aperture of 2.8 usually provides optimal image quality at apertures of 4-5.6. When the aperture is closed strongly (f-number greater than 5 for compact devices and 11 for DSLRs), the resolution decreases due to diffraction. These effects are not to be feared, but they must be kept in mind.

Q: Why does the camera set very slow shutter speeds when shooting with flash (the image is blurry)?
A:
The unit is in slow flash sync mode. It is used when the photographer wants to make the most of external light sources, with flash light as an auxiliary light. For example, if you need to slightly highlight the shadows, or when shooting at night, in order to better work out the background with lights, and illuminate the important detail in the foreground with a flash. In this mode, you usually have to use a tripod or other solid camera support.

For "normal" flash photography, you need to disable this mode. Refer to the instruction manual for the DSC or flash.

PHOTO PROCESSING

Q: How to process RAW file?
A:
The most affordable way is to use the converter that comes with the camera. But often such converters do not shine with speed, quality, or functionality...

The main third-party and most versatile program used in most free and commercial converters is , written by Dave Coffin. This program allows you to convert all official and most service RAW files. One of the most successful graphical interfaces of this program supporting Unix, Mac and Windows -

Q: Is it possible to remove noise from photos?
A:
Yes, you can. Removing noise always reduces the resolution of images, since fine details of the image fall under the knife along with the noise. The greater the degree of noise reduction, the more the resolution suffers, so when processing, you should look for a compromise between noise and “soapiness” of the picture.

You can reduce noise during in-camera processing, in the RAW converter and in image editors. The best results are obtained by using specialized noise removal programs such as.

When processing an image, sharpening should always be done after noise reduction!

Q: How to fix a blurry photo?
A:
No way. If the photo is blurry, then it is impossible to make it sharp - no filter can come up with details that are not in the image. You can try to increase the apparent sharpness using stronger sharpening, but this does not help in the case of hopelessly blurry images. However, if the lens itself produces a blurry picture, then increasing the sharpening (within reasonable limits) can improve the impression of the photo.

Note. Sharpening is the process of sharpening the edges of an image. In this case, the picture begins to seem clearer, although in fact the real resolution has not changed. Sharpening emphasizes noise and, if used excessively, leads to the appearance of artifacts. However, it is always used when processing images with in-camera software.

. They have Lossless JPEG Transform operations, where you can not only rotate a photo, but also mirror it. This operation can be carried out with a group of selected images, and you can overwrite the original files or save the result to another folder.

Also, if the camera contains an orientation sensor and writes the orientation information of the picture in the EXIF ​​header, you can select all the pictures and press a button that rotates the picture according to the orientation information in the EXIF ​​header. It should be noted that such a sensor is not available in all DSCs.

The lossless rotation feature is also available in other programs. For example, - is specifically designed to process (not only rotate) JPEG files, as losslessly as possible. Program discussion.

Q: How to take a panoramic photo?
A:
Many modern DSCs have a special mode for shooting panoramas. If this mode is not available, then you should use full manual control of the camera (including WB, focus and exposure - no automation!). Frames that will be included in the panorama should preferably be taken in vertical orientation and not at the extreme values ​​of the focal length of the lens. The use of a tripod is highly recommended. The overlap of adjacent frames should be approximately 1/3-1/2. For gluing panoramas, you can use both conventional image editors (they give better results at a great expense of time) and specialized programs (usually they are included in the CPC delivery package).

One of the most powerful programs for stitching panoramas is free and supports all popular operating systems, however, it is very difficult to use, so it is recommended to use one of the available free shells, for example,.

Panoramas can also be taken with specially adapted cameras. Read about one of them on our website.

Q: How do I store my digital photo archive?
A:
No hard drive is immune from failures and total data loss. Therefore, it is always recommended to make (and regularly update) a backup copy of the photo archive on optical media (CD-R, DVD-R, DVD+R). In this case, it is not recommended to use the "latest" (read - "raw") technologies and maximum recording speeds (for CD-R). You should also stay away from rewritable (...-RW) media. One of the best programs for burning discs - Nero Burning Rom. With the help of application programs for Nero Burning Rom, you can also check discs for errors and, if necessary, rewrite. There are many free programs, practically not inferior to it when performing the main tasks: , .

To store and view photos on your hard drive, it makes sense to use a folder system sorted by subject. And a separate folder - for RAW.

Q: How can I make a slideshow of my photos for a computer or DVD player?
A:
Most image viewers have the ability to work in slideshow mode. In addition, for slide show creation you can use the program Microsoft PowerPoint from the Office package.

If you want to view photos on a TV, you should be aware that many modern DVD players support viewing images in JPEG format. All you need to do is convert photos to JPEG at least 720x576 in size (it doesn't make sense to do much more) and burn them to disk. In addition, DVD-presentations can be created in specialized programs.

TECHNICAL QUESTIONS

Q: Can the DSC be used as a webcam?
A:
Some digital cameras have this capability and this should be stated in the manual. Note that DSCs of the world's leading manufacturers very rarely allow you to work in the webcam mode. Rather, you can find this feature in multifunctional, not very high-quality devices under the brands Genius, Aiptek, UFO, etc.

Even if your DSC does not support webcam mode, you can connect its video output to the input of a video capture card or TV tuner (if available). In this case, the quality may be unsatisfactory (a small number of frames per second), and unnecessary service information (battery charge level, etc.) will be displayed on the screen. In this case, compatibility issues with videoconferencing software are determined by the video capture cards used, not by the camera.

Consider using your expensive digital camera as a replacement for a specialized device that has already dropped to a reasonable $25-30!

Q: Is it possible to use DSC for reshooting and subsequent text recognition? What pre-processing of images is better to do for better recognition?
A:
Yes, you can. This will require a camera with a matrix resolution of at least 4 megapixels, as well as subsequent image processing in a graphics editor. It should be noted that any flatbed scanner will provide higher quality and convenience, but the main advantage of the DSC is its mobility and the ability to use it to recognize texts that cannot be scanned (for example, wall ads).

The first stage - shooting:

  1. It is best to use a tripod if you have one and if you are shooting at home (or where a tripod can be used). It is better not to use the flash, as it usually "whitens" the letters, and part of the text may simply disappear. In any case, it gives uneven lighting. In addition, a tripod allows you to set the camera in relation to the text as evenly and without distortions as possible.
  2. In order for the page to occupy the maximum possible frame area, you need to use the zoom (optical, of course). It is also better to do this because on all DSCs (especially on ultrazooms and ultracompacts) there are noticeable barrel-shaped distortions at a wide angle. At the average zoom value, they are usually practically absent.
  3. Reshoot all pages in maximum quality and copy them to your computer. If the shooting was carried out in such a way that the frames turned out to be differently rotated, bring them to the same orientation (so that later you can use batch processing for all frames at once).

The second stage is preparing images for better recognition:

  1. First, convert the image to grayscale mode (color is usually not needed anyway, and b / w mode increases the speed of post-processing).
  2. Make the background uniform in brightness by applying the Highpass filter. You can also increase the image size by 2 times (the subsequent steps will work better).
  3. With the help of Levels/Curves, kill several birds with one stone: remove noise, make the background absolutely white, increase the contrast, make too bold letters thinner and better distinguishable.
  4. Use the Unsharp mask to increase the edge sharpness and sharpen the letters.

You can select the parameters of each stage for the first page once, and process all the rest automatically using actions / batch processing (to do this, you need to write all actions in Action in Photoshop). All this, of course, provided that the lighting did not change during the shooting.

Q: Can the camera and microscope (telescope) be connected?
A:
Yes, you can. The simplest and least qualitative way is to focus the DPC to infinity, fix the focus and bring the camera lens to the telescope eyepiece, and then finally focus the system manually using the telescope's focusing devices. If higher image quality is needed, equipment is needed to rigidly mount the apparatus to the telescope, ensuring that the optical axes of both instruments coincide (the usual place of production is the nearest locksmith's shop). The focal length will be equal to the FR of the lens of the apparatus, multiplied by the magnification of the optical device; aperture is determined by the diameter of the lens of the optical device. That is, a 20x Tourist-3 tube is capable of turning an EF-S 18-55 into an EF-S 360-1100, but with an aperture ratio of 7.2-22. Accordingly, be prepared for all the “charms” of an ultra-long focus at a fixed aperture, and at the same time for image blur due to the movement of air masses.

Cameras with interchangeable lenses, in addition to shooting through the eyepiece, allow you to shoot in the main focus; to connect the apparatus to the telescope, either factory adapters are used (they are also “T-mount”, available for all common diameters of eyepieces and threads / mounts), or products from a locksmith workshop, pasted over with velvet black paper from the inside.

The same tasks can be solved with the help of Soviet MTO or Rubinar telephoto lenses and adapters from the M42 thread to the corresponding mirror CFC mount. Their focal lengths reach up to 1000 mm, which can suit an amateur astronomer.

With any method of shooting, it should be borne in mind that telescopes, spotting scopes and binoculars are focused on visual observations and therefore, when paired with a camera lens, they can give noticeable HA and astigmatism.

The issue of connecting a camera with optical devices is discussed in detail in the article "Kepler's tube - a macroconverter and a photo gun in one bottle". Optical schemes for different methods of shooting through a microscope are discussed in the article: "Flea glass" in a modern version.

Q: How to make a photo gallery on the Internet?
A:
You should distinguish what you are doing a photo gallery for.

It's one thing - if you just want to post various photos on the Web in large quantities, and their quality can be anything. . You can also use the service. A free account allows you to upload photos in any quantity and any size, but their total size should not exceed 10 MB, and the ability to upload photos exists only for 1 month after creating an account. However, no one bothers to create several accounts in turn, indicating fictitious addresses Email. Another way is to create a site on a free hosting, but this requires additional qualifications in a related field :-).

If you want your the best photos not only saw, but also appreciated, then you should pay attention to one of the photo sites, for example, or. It's kind of " virtual exhibitions”, so they have restrictions on the number and size of uploaded photos (to avoid clogging). Only photographs of artistic value should be posted on such sites, otherwise bad ratings are inevitable.

Q: Where can I find the Russian manual for my camera?
A:
"Official" instructions can usually be found on the manufacturer's support site. Some firms (for example, Canon) do not post instructions on the Internet, and therefore you have to look for options that are independently scanned and posted on the Web by enthusiasts. There is no single free "repository" of instructions in Runet, so you need to use a search on the Internet or on this conference with the keywords "instruction" and "[your CFC model]".

Q: Is it true that out of two camera models with the same number of megapixels, the one with the higher dpi (dots per inch) has a higher resolution?
A:
Not true. Pixels per inch is only meaningful when printing images on paper. The values ​​shown by image viewers are taken from the image's metadata in the EXIF ​​header. Different cameras write different numbers in the "resolution" field in this header, just to follow the EXIF ​​header standard, according to which some kind of resolution must be indicated there.

The most common value is 72 dpi, which corresponds to the standard resolution of a CRT monitor. A picture from the DSC can be printed on different paper sizes, and only this will determine what real resolution will be obtained when printing. For example, a 5 megapixel image can be printed with a size of 10×15 cm, while the actual print resolution will be more than 400 dpi. But if it is printed with a format of 20 × 30 cm, then the print resolution will be 2 times less.

Q: What devices are used in the DSC to fix the image instead of film?
A:
The most common type of sensor used in modern DPCs is a CCD matrix (charge-coupled device, in English CCD - short for charge-coupled device).

A number of digital SLR cameras use a CMOS or CMOS sensor (complementary metal-oxide-semiconductor), memory chips are also made using this technology.

Other types of sensors (Foveon, LBCAST) are used less often, although they have some advantages over both CCD and CMOS (but also have disadvantages).

Q: What is "digital zoom" and what is it for?
A:
In fact, this is a purely marketing "feature" that allows manufacturers to attract an inexperienced buyer with the help of huge values zoom. Digital zoom is strictly not recommended when shooting, since the zoom effect is achieved by cutting out a piece of the image and stretching it to its original size. In this case, the quality deteriorates quite a lot (just like when viewing photos at a scale greater than 100%).

You can allow the use of digital zoom only when shooting video, and also if you shoot in JPEG with a reduced resolution (then a piece is simply cut out of the frame without stretching). In all other cases, digital zoom is strongly recommended to be disabled in the menu.

The compiler expresses his gratitude to the participants of the iXBT conference, without whose help the creation of this FAQ would not have been possible.


Man has always been drawn to the beautiful, the beauty he saw, the man tried to give shape. In poetry, it was a form of words, in music, beauty had a harmonic sound basis, in painting, the forms of beauty were conveyed by colors and colors. The only thing a person could not do was capture the moment. For example, to catch a breaking drop of water or lightning that cuts through a stormy sky. With the advent of the camera and the development of photography, this became possible. The history of photography knows multiple attempts to invent the photographic process before the creation of the first photograph and dates back to the distant past, when mathematicians studying the optics of light refraction discovered that the image turns upside down if it is passed into a dark room through a small hole.

In 1604, the German astronomer Johannes Kepler established the mathematical laws of light reflection in mirrors, which later formed the basis of the theory of lenses, according to which another Italian physicist Galileo Galilei created the first telescope for observing celestial bodies. The principle of refraction of rays was established, it only remained to learn how to somehow preserve the resulting images on prints by a chemical method that had not yet been discovered.

In the 1820s, Joseph Nicéphore Niépce discovered a way to preserve the resulting image by treating the incident light with asphalt varnish (analogous to bitumen) on a glass surface in the so-called camera obscura. With the help of asphalt varnish, the image took shape and became visible. For the first time in the history of mankind, a picture was painted not by an artist, but by falling rays of light in refraction.

In 1835, the English physicist William Talbot, studying the possibilities of Niépce's camera obscura, was able to achieve an improvement in the quality of photographic images using the print of a photograph invented by him - a negative. Thanks to this new opportunity pictures can now be copied. In his first photograph, Talbot captured his own window, which clearly shows the window bars. In the future, he wrote a report where he called artistic photography the world of beauty, thus laying in the history of photography the future principle of printing photographs. In 1861, English photographer T. Setton invented the first camera with a single reflex lens. The scheme of operation of the first camera was as follows, a large box with a lid on top was fixed on a tripod, through which light did not penetrate, but through which it was possible to observe. The lens caught focus on the glass, where the image was formed with the help of mirrors.

In 1889, the name of George Eastman Kodak is fixed in the history of photography, who patented the first film in the form of a roll, and then the Kodak camera, designed specifically for film. Subsequently, the name "Kodak" became the brand of the future large company. Interestingly, the name does not have a strong semantic load, in this case, Eastman decided to come up with a word that begins and ends with the same letter.

In 1904, the Lumiere brothers, under the trademark "Lumiere", began to produce plates for color photography, which became the founders of the future of color photography. .

In 1923, the first camera appears, which uses 35 mm film, taken from the cinema. Now it was possible to get small negatives, then looking through them to choose the most suitable for printing large photographs. After 2 years, Leica cameras are launched into mass production.

In 1935, Leica 2 cameras were equipped with a separate viewfinder, a powerful focusing system that combined two pictures into one. A little later, in the new Leica 3 cameras, it becomes possible to use the shutter speed control. For many years, Leica cameras have been an indispensable tool in the field of photography in the world.

In 1935, the Kodak company mass-produced Kodakchrom color photographic films. But for a long time, when printing, they had to be sent for revision after development, where color components were already superimposed during development.

In 1942, Kodak launched Kodakcolor color film, which for the next half century became one of the most popular films for professional and amateur cameras.

In 1963, the idea of fast printing photos are flipped by "Polaroid" cameras, where the photo is printed instantly after the received picture with one click. It was enough just to wait a few minutes for the outlines of the images to begin to be drawn on the blank print, and then a good quality full color photo showed through. For another 30 years, versatile Polaroid cameras will occupy the leading places in the history of photography in popularity, to give way to an era digital photography.

In the 1970s cameras were equipped with a built-in exposure meter, autofocus, automatic shooting modes, amateur 35 mm cameras had a built-in flash. A little later, by the 80s, cameras began to be equipped with LCD panels that showed the user the software settings and camera modes. The era of digital technology was just beginning.

In 1974, the first digital photograph of the starry sky was obtained using an electronic astronomical telescope.

In 1980, Sony prepares to launch the Mavica digital video camera on the market. The captured video was saved on a floppy disk, which could be erased indefinitely for a new recording.

In 1988, Fujifilm officially launched the first Fuji DS1P digital camera, where photographs were stored digitally on electronic media. The camera had 16Mb of internal memory.

In 1991, Kodak released the Kodak DCS10 digital SLR camera, which has 1.3 mp resolution and a set of ready-made functions for professional digital shooting.

In 1994, Canon introduced optical image stabilization to some of its cameras.

In 1995, Kodak, following Canon, ceased production of its branded film cameras, which have been popular for the last half century.

2000s Rapidly developing on the basis digital technologies corporations Sony, Samsung absorb most of the digital camera market. New amateur digital cameras quickly overcame the 3-megapixel technological frontier and easily compete with professional photographic equipment in size from 7 to 12 megapixels in terms of matrix size. In spite of fast development technologies in digital technology, such as: face detection in the frame, skin tone correction, red-eye removal, 28x zoom, automatic shooting scenes and even triggering the camera at the moment of a smile in the frame, the average price in the digital camera market continues to fall, especially since in the amateur segment, cameras have begun to resist mobile phones with built-in digital zoom cameras. Demand for film cameras has plummeted and now there is another upward trend in the price of analog photography, which is becoming a rarity.



Film camera device

The principle of operation of an analog camera: light passes through the aperture of the lens and, reacting with the chemical elements of the film, is stored on the film. Depending on the lens optics setting, the use of special lenses, the illumination and the angle of the directed light, the aperture opening time can be obtained different kind images on the photo. From this and many other factors, the artistic style of photography is formed. Of course, the main criterion for evaluating a photo is the look and artistic taste of the photographer.

Frame.
The body of the camera does not transmit light, has mounts for the lens and flash, a convenient grip shape and a place for attaching to a tripod. A photographic film is placed inside the case, which is securely closed with a light-tight cover.


Film channel.
In it, the film is rewound, stopping at the frame you need to shoot. The counter is mechanically linked to the film channel, which, when scrolled, indicates the number of shots taken. There are motor-driven cameras that allow you to shoot through a sequentially set period of time, as well as to shoot at high speed up to several frames per second.


Viewfinder.
An optical lens through which the photographer sees the future frame in the frame. It often has additional marks to determine the position of the object and some scales for adjusting the light and contrast.

Lens.
A lens is a powerful optical device consisting of several lenses that allows you to take images at different distances with a change in focus. Lenses for professional photography, in addition to lenses, also consist of mirrors. A standard lens has a focus distance rounded equal to the diagonal of the frame, an angle of 45 degrees. The focal length of a wide-angle lens smaller than the diagonal of the frame is used for shooting in a small space, an angle of up to 100 degrees. for distant and panoramic objects, a telescopic lens is used whose focal length is much larger than the diagonal of the frame.

Diaphragm.

A device that regulates the brightness of an optical image of a photographed object in relation to its brightness. The most widespread is the iris diaphragm, in which the light hole is formed by several crescent-shaped petals in the form of arcs; when shooting, the petals converge or diverge, reducing or increasing the diameter of the light hole.

Gate

The camera shutter opens the shutters to allow light to hit the film, then the light begins to act on the film, entering into a chemical reaction. The exposure of the frame depends on the duration of the shutter opening. So for night shooting, a longer shutter speed is set, for shooting in the sun or high-speed shooting, it is as short as possible.





Rangefinder.

The device by which the photographer determines the distance to the subject. often the rangefinder is combined for convenience with the viewfinder.

Release button.

Starts the process of taking pictures, lasting no more than a second. In an instant, the shutter is released, the aperture blades open, light hits the chemical composition of the film, and the frame is captured. In older film cameras, the shutter button is based on a mechanical drive, in more modern cameras, the shutter button, like the rest of the moving elements of the camera, is electrically driven.


Film reel
The reel on which the film is attached inside the camera body. At the end of the frames on the film in mechanical models, the user rewound the film in the opposite direction manually, in more modern cameras the film was rewound at the end using an electromotor drive powered by AA batteries.


Photo flash.
Poor lighting of photographic subjects leads to the use of flash. V professional photography this has to be resorted to only in urgent cases when there are no other devices for illuminating screens, lamps. The flashlight consists of a gas-discharge lamp in the form of a glass tube containing xenon gas. When energy is accumulated, the flash is charged, the gas in the glass tube is ionized, then instantly discharged, creating a bright flash with a light intensity of over a hundred thousand candles. During flash operation, the effect of "red eyes" in people and animals is often noted. This is because when the room where the photograph is taken is insufficiently lit, the person’s eyes expand and when the flash fires, the pupils do not have time to narrow, reflecting too much light from the eyeball. To eliminate the effect of "red-eye", one of the methods is used to pre-direct the light flux to the person's eyes before the flash fires, which causes a narrowing of the pupil and less reflection of the flash light from it.

Digital camera device


The principle of operation of a digital camera at the stage of light passing through the objective lens is the same as that of a film camera. The image is refracted through the optics system, but is not stored on the chemical element of the film in an analog way, but is converted into digital information on the matrix, the resolution of which will determine the quality of the image. The recoded image is then digitally stored on a removable storage medium. Information in the form of an image can be edited, overwritten and sent to other storage media.

Frame.

The body of a digital camera looks similar to a film camera, but due to the lack of a film channel and a place for a film reel, the body of a modern digital camera is much thinner than a conventional film camera and has room for an LCD screen built into the body or a retractable one, and slots for memory cards.

Viewfinder. Menu. Settings (LCD) .

The liquid crystal screen is an integral part of a digital camera. It has a combined viewfinder function in which you can zoom in on the subject, see the result of autofocus, adjust the exposure to the edges, and also use it as a menu screen with settings and options for a set of shooting functions.

Lens.

In professional digital cameras, the lens is practically no different from analog cameras. It also consists of lenses and a set of mirrors and has the same mechanical functions. In amateur cameras, the lens has become much smaller and, in addition to the optical zoom (approaching an object), it has a built-in digital zoom that can bring a distant object many times closer.

Matrix sensor.

The main element of a digital camera is a small plate with conductors that forms the image quality, the clarity of which depends on the resolution of the matrix.

Microprocessor.

Responsible for all functions of the digital camera. All camera control levers lead to the processor in which the software shell (firmware) is sewn, which is responsible for the camera's actions: viewfinder operation, autofocus, program shooting scenes, settings and functions, electric drive of a retractable lens, flash operation.

Image stabilizer.

If you shake the camera while pressing the shutter shutter, or when shooting from a moving surface such as a boat bobbing in the waves, the image may be blurred. The optical stabilizer practically does not degrade the quality of the resulting image due to additional optics, which compensates for image deviations during swaying, leaving the image motionless in front of the matrix. The scheme of operation of the digital image stabilizer of the camera when the image is shaking consists in conditional corrections made when calculating the image by the processor, using an additional third of the pixels on the matrix that are involved only in image correction.

Information carriers.

The resulting image is stored in the camera's memory as information on the internal or external memory. The cameras have slots for SD, MMC, CF, XD-Picture, etc. memory cards, as well as slots for connecting to other sources of information storage, a computer, HDD, removable media, etc.

Digital photography has greatly changed the idea in the history of photography about what an artistic photo should be. If in the old days the photographer had to go to various tricks to get an interesting color or an unusual focus to define the genre of photography, now there is a whole set of gadgets included in digital camera software, image size correction, color changing, creating a frame around the photo. Also, any captured digital photo can be edited in well-known photo editors on a computer and easily installed in a digital photo frame, which, following the step-by-step advance of digital technologies, are becoming more and more popular for decorating the interior with something new and unusual.

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