Just recently I started to take pictures with a DSLR, namely the Canon EOS 500D. With such a camera, you can decide in which file format you would like to save your photos. While I don’t want to go into detail here, or even worse, start a flame war about which one is the best, I would like to tell you why I chose to work with RAW.

If you don’t know what these file types are, or you would like to find out more about them, I’d suggest you’d read about them on Wikipedia, for example.

So why am I using RAW? Firstly, my Canon saves files in it’s proprietary *.cr2 file type which means it’s already a RAW format and therefore needs no conversion. Secondly, RAW has all the benefits I like, such as editing a photo without the original file actually being changed. No reason to choose RAW+JPG or just JPG either. While the argument continues whether or not the camera-made conversion to JPG actually is good enough, I personally don’t mind the extra space the RAW photos take. Besides, when editing a JPG, the original file will be changed, which raises the need to save one photo several times. But what about DNG? I wasn’t sure. It sounded just too good to be true. Having all the positive aspects of the RAW format, no extra XMP files to drag around and also saving disk space are clear plus points for this format.

After thinking about it a while though, I decided against it because of the following reasons:

- I need to convert every photo I have and will have to do so in the future.
- Converting files may end up in corrupted files, which adds the need to re-check if all went well.
- Adding the RAW file to the DNG container, will double the space needed in comparison to just RAW.
- The question whether or not Adobe will continue supporting and pushing this format.
- All changes are written into the file directly.

All changes are written into the file… Believe it or not, that is the major reason for me to stick with RAW. Having an extra file to carry around sounds like lots of trouble, but since I’m using an online backup solution, I like that a lot.

Like other backup solutions, Backblaze or Mozy (for example) will regularly look for files that have changed and make a backup of them. Now, whenever changing a tag, the exposure or other settings, the backup software will think I changed the file and make a backup. Since even DNGs can easily have 15Mbyte/photo, this adds up quickly. With a tiny XMP in comparison though (around 8kbyte), I can change the photos as much as I want to, without having to fear my upload bandwith being blocked for days or even weeks, as the RAW files themselves never change.

Other thoughts or opinions on this matter are always welcome in the comments. :)