I've been annoyed with the lack of RAW support for the Canon EOS 350D for a long time, and had high hopes that 10.4.3 would fix this, as it seemed to be the OS version that Aperture was waiting for. However, I was dismayed to find that 10.4.3 still hasn't gotten it right. After some prodding, I went and delved into the update's .pax file, and found an interesting file called Raw.plist, which has a list of all the RAW formats that the system supports.
To my astonishment, there is already support for the Canon EOS Digital Rebel XT, which is simply the US name for the 350D: looking closely at the statements showed that it was likely to be the ASCII string that the RAW importer was searching for, so after a quick strings on one of my RAW, files I simply copied the XT section and renamed the initial key to Canon-EOS 350D DIGITAL, and now both iPhoto and Preview understand my files. I've no idea if this was actually in an earlier 10.4 release (my guess is that not long after the 20D was added, the XT support would have gone in.
So if you want EOS 350D RAW support, here's what to do. Add this chunk of XML to the file Raw.plist, which is found in this directory (formatted for copy-and-paste into the Terminal):
/System/Library/Frameworks/ApplicationServices.framework/\
Versions/A/Frameworks/ImageIO.framework/Versions/A/Resources
You will need Administrator rights to alter this file, of course.
Mac OS X Hints
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