Why Shoot in RAW

Many amateur photographers having digital SLR cameras or some of the more sophisticated compact models often ask the question why you need to shoot in RAW. In fact it is a widespread belief that using RAW-format only complicates your life. This - of course - is only half true.

If you own a DSLR, not by accident and before posting or printing your image you'd like to get the most out of what your camera and your computer software are able of, and exercise some creative thinking, then the right question is not whether to shoot in RAW, but exactly how to do it.

Shooting in RAW gives the photographer the power of processing of the image after it has been captured by the digital camera sensor or the so called postprocessing.

RAW-files for digital photography are what unprocessed film is to the film ones. The dark room is actually the computer and the software you prefer to use. Shooting in RAW has many advantages, but the most important ones are:

* Editing the image without loss of quality and risk of disruption its original appearance
* Ability to make significant adjustments to the exposure so as to correct overexposed or underexposed images or parts of them
* Adjusting the white balance
* Ability to clear color noise, even before you open an image file from the RAW-file
* Ability to adjust chromatic aberrations
* Neglect of all camera settings, if necessary


RAW-image, is not actually an image - it is rather a set of data that the camera sensor has created based on the captured light. To see this image on your computer screen, the data should be transformed to the traditional RGB values so it can be stored as a TIFF, JPEG or any other image file format.

Adjusting your camera to shoot in JPEG practically means that you leave your camera to make all these adjustments for you: to "process" your "digital film" and turn it into a picture as "administered" by the pre-settings like contrast, white balance, sharpness and color. Shooting in JPEG, really means that you authorize your camera to be your photo laboratory. Once recorded in the JPEG-image, these settings are combined in RGB-data irreversibly and from that moment on your ability to influence in any way (especially non-destructive) the picture is very limited. If you've used the wrong white balance, this error will be seen in the final result and it will be far more difficult to repair compared to if you had the original "raw" data set from the sensor, where the information is not yet implemented. Yeah, right - no mistake - the RAW doesn't contain any attached information on color, contrast and sharpness. This information is only metadata that can be taken into account during the processing or ignored completely. The chosen by you settings are applied to the image only when it is converted to RGB-bitmap.

Unlike editing bitmap images when editing RAW-file we do not change the data in it, we just interpret it differently. This enables us to edit RAW-files as many times as we want, without the risk of immediate destruction of information and without loss of quality. Otherwise, it is enough to change the contrast or color of the JPEG-file, and save the changes and there's no way back if you have not made a copy of your file before the intervention.

Of course, shooting in RAW has it's price. You won't be able to simply send the contents of your card to friends without first complete processing, which will take much time, effort and computing power. RAW-files are usually large and require significant resources from your computer. A 6-megapixel Nikon D70s makes 6-megabytes per image file. With Nikon D2X, for example, we should expect no less than 19 megabytes file. Accordingly, you'll need a quite large memory card in order to shoot more than a few pictures.

AS far as different sensors and methods to interpret the data to RGB are used, each manufacturer typically uses a different RAW-format. Nikon calls its RAW-format Nikon Electronic Format or NEF as an abbreviation. This format offers as an option of "visually invisible "compression to reduce the file size. If you're shooting with a D50 or D70 you can use uncompressed NEF. With the DSLR-s higher-grade Nikon you can choose between compressed and uncompressed NEF. If you have a large enough memory card uncompressed NEF absolutely guarantees you the best possible image quality. In real tests, however, is virtually impossible to detect differences between compressed and uncompressed NEF, so that the use of compression should not bother you.

The software, which makes the bitmap conversion possible is called RAW-converter and is mandatory preliminary step before opening your photos in your favorite image editing software. Such tools are Adobe Camera Raw (plug-in to Photoshop), Adobe Lightroom, Apple Aperture, Pixmantec RawShooter, Bibble Raw, Phase One or such provided by the manufacturer of your camera.