Echostrung wrote in post #7399073
I believe only the new photoshop (cs4) is able to open it. You may need to download the new raw update on the adobe website even for cs4 to open it.
The 50D will work just fine with Photoshop CS3. If you are using an earlier version then you have to jump through a few hoops to get it to work.
If you have CS3 and it won't read the file, then you need to apply the update so you can get the 4.6 version of ACR that is compatible with the 50D. This is as simple as clicking on the help pulldown and choosing update. If you have never done this then you are missing out on quite a bit.
If you are using Photoshop CS2 or CS1, then you might consider upgrading, or get a copy of Lightroom. The alternate method is to convert the raw file into Adobe DNG format buy using the converter. Do a seach on Adobe for the download link.
I use my 50D with CS3 and don't have any problem with it. I am giving CS4 a try as there has been threads that say the 4.6 ACR doesn't work well with the 50D with noise. Thought I would try it out for myself it see if there is any merrit to the rumblings.
Matt.