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Information on image formats
All images are shot exclusively in the camera 'RAW' image format, the following information explains why.
Basically, camera 'RAW' images are far superior in quallity than a camera 'JPG' which has been processed in camera....
...it's all about quality!
RAW V's. JPEG
The idea of a raw file is to preserve all of the sensor data captured by the camera. No conversion processing is done inside the camera; so all processing is deferred until the raw file is downloaded to a PC.
This is in great contrast to a camera JPEG where all the conversion processing is done inside the camera, including things such as white balance, tonal range, contrast, saturation and sharpening, etc. This process is irreversible, so if the camera white balance, for example, was set wrong, it may be tricky to adjust in Photoshop, whereas, in most raw converters, changing the white balance is trivial.
Worse yet, the 12-bits per pixel of sensor data is truncated to 8-bits for the JPEG conversion. Also, JPEG uses lossy compression to reduce file size, which means it discards some additional colour information as a trade-off for smaller files. Consequently, JPEG may produce some artifacts, such as halos around dark objects contrasted against a bright background. The artifacts can be worsened later during post-processing such as sharpening.
Basically, shooting and capturing in JPEG is fine for the consumer or amature who does not want to “develop” his own film and is used by some professionals who are satisfied that JPEG suits their requirements.
However, professional photographers have traditionally always done their own processing and printing to get the absolute best results by having control over every step in the photography process, and do not allow the camera to do processing that they prefer to defer until later.
A rough comparison is Polaroid vs. regular film, or taking the film to the local drugstore instead of using a professional lab to process and print it.
Working with Digital Camera Raw Images
Why even bother with digital camera raw images when the camera will output a JPEG image, complete with its ICC colour profile embedded? To answer the question, let's look at the steps used to convert a raw image to a print.
Digital photographers call the particular procedure they use a “workflow.”
A raw image from a digital camera could be a 16-bit TIFF file, or it could be a proprietary compressed format that is lossless, preserving all the sensor data. Since most digital cameras record 12 bits of colour data per pixel, the raw file preserves all 12 bits. Once a raw file is converted to TIFF, it is quite large. For example, a six-megapixel Canon 10D image that is 3072 x 2048 pixels requires about six MB for RAW format, and 36 MB for a 16-bit TIFF file, therefore RAW data requires less space on media cards.
Finally...
I recommend that images are saved as TIFF's to preserve all information, however, even if images are finally saved as JPG's they will still be superior in quality to those processed internally by the camera!
