2. Are all raw files the same?
No, and this is where much of the confusion surrounding raw files starts. Unlike JPEGs, there isn’t a standard for the raw files produced by most of the cameras made by big-name manufacturers.
Each manufacturer has its own raw file format, and even more confusingly each model of camera has its own version of this format.
So, current Canon cameras will produce a raw file with a .cr2 suffix, and the raw file from an EOS 1100D SLR will actually be slightly different to one from an EOS 7D.
In use, these differences are only relevant if you’re editing files from more than one camera, or have updated your camera without installing new software on your PC, as the way that they work (and the way that you use them) will be the same.
To further confuse matters, there is an exception to this rule. DNG is a file format developed by Adobe, which can be used by any manufacturer, but of the main SLR manufacturers only Pentax has included it on its cameras.
Even if you use another brand of camera, DNG can still be a useful format, because it can be used as a way of opening raw images from new cameras in old versions of Photoshop and Elements.
3. Why can’t I view raw files on my computer without using special software?
Because a raw file is just a package of data – your computer doesn’t know what to do with it. Unlike a standard format, such as JPEG, a raw file doesn’t contain the information needed for your PC to decode it.
Think of it like the words on a page: JPEG is like the finished article containing words, paragraphs and all of the correct punctuation; raw is like having all of the same letters written down, but not necessarily in the same order and without a structure that you can easily understand.