Basics of Raw (CR2) Format for the Canon Rebel T5/1200D - dummies

Basics of Raw (CR2) Format for the Canon Rebel T5/1200D

By Julie Adair King, Robert Correll

Another picture-file type that you can create with your Canon Rebel T5/1200D is Camera Raw, or just Raw (as in uncooked) for short. Each manufacturer has its own flavor of Raw files; Canon’s are CR2 files (or, on some older cameras, CRW). Raw is popular with many advanced photographers for these reasons:

  • Greater creative control: With JPEG, internal camera software tweaks your images, adjusting color, exposure, and sharpness as needed to produce the results that Canon believes its customers prefer. With Raw, the camera simply records the original, unprocessed image data. The photographer then copies the image file to the computer and uses software known as a raw converter to produce the actual image.

  • More flexibility: Having access to the Raw photo data means that you can re-process the same photo with different settings over and over again without losing any quality.

  • Higher bit depth: Bit depth is a measure of how many color values an image file can contain. JPEG files restrict you to 8 bits each for the red, blue, and green color components, or channels, for a total of 24 bits. That translates to roughly 16.7 million possible colors. On your camera, a Raw file delivers a higher bit count, collecting 14 bits per channel.

    Although jumping from 8 to 14 bits sounds like a huge difference, you may not ever notice any difference in your photos — that 8-bit palette of 16.7 million values is more than enough for superb images. Where having the extra bits can come in handy is if you really need to adjust exposure, contrast, or color after the shot in your photo-editing program.

    In cases where you apply extreme adjustments, having the extra original bits sometimes helps avoid a problem known as banding or posterization, which creates abrupt color breaks where you should see smooth, seamless transitions. (A higher bit depth doesn’t always prevent the problem, however, so don’t expect miracles.)

  • Best picture quality: Because Raw doesn’t apply the destructive compression associated with JPEG, you don’t run the risk of the artifacting that can occur with JPEG.

But just like JPEG, Raw isn’t without its disadvantages:

  • You can’t do much with your pictures until you process them in a Raw converter. You can’t share them online, for example, or put them into a text document or multimedia presentation. So when you shoot Raw, you add to the time you spend in front of the computer instead of behind the camera lens.

  • Raw files are larger than JPEG files. Unlike JPEG, Raw doesn’t apply lossy compression to shrink files. This means that Raw files are significantly larger than JPEG files, so they take up more room on your memory card and on your computer’s hard drive or other file-storage devices.

Whether the upside of Raw outweighs the down is a decision that you need to ponder based on your photographic needs, schedule, and computer-comfort level. If you decide to try Raw shooting, you can select from the following Image Quality options:

  • RAW: This setting produces a single Raw file at the maximum resolution (18MP).

  • RAW+Large/Fine: This setting produces two files: the Raw file plus a JPEG file captured at the Large/Fine setting. The advantage is that you can share the JPEG online or get prints made immediately and then process your Raw files when you have time. The downside, of course, is that creating two files for every image eats up substantially more space on your memory card and your computer’s hard drive.