Finder doesn't show thumbnail previews for RAW files Since I upgraded to Lion (10.7.5), Finder doesn't display thumbnail previews of ARW files. ARW is a Sony RAW image format (in my case files were produced by Sony NEX-5 camera). Finder used to display the thumbnails under Snow Leopard (10.6.8), but not anymore. ARW files are opened as usual by the Preview app, their previews are shown in the Finder preview column and by Quick Look. Only the thumbnails are not shown.

I've googled and found this is a well-known issue but unfortunately there is no reliable solution. Somebody fixed it by removing Finder preferences files (~/Library/Preferences/com.apple.finder.*), somebody by installing latest versions of iPhoto and "RAW Compatibility Update" and somebody reported it was only fixed for him in ML 10.8.2 update.

So far I have:


Fixed the permissions on system drive
Removed Finder preferences files and restarted the Finder
Installed updates for iPhoto (9.4.3) and RAW Compatibility Update (4.05)
Danced with a shaman's tambourine


But still no luck. Any thoughts? Is upgrade to Moutain Lion my only choice? And will it indeed help?
Raw support for cameras is something that changes with almost every OS update. Specifically, Lion 10.7.0 only supports some cameras, and 10.7.1 adds more, and so on. Also, according to this KB article on what cameras Apple supports - it is similarly vague that you need specific versions of Aperture or iPhoto to even see whether your machine needs a RAW camera support update.


http://support.apple.com/kb/HT4757


So, it looks like Apple is adding raw support to the OS in combination with you having a new enough version of either iPhoto or Aperture. I would say, you might want so jump to 10.8.3 and install the latest iPhoto from the Mac App store since my feeling is Lion intentionally changed RAW processing to exclude anything it wasn't sure it supported instead of 10.6's we'll try to draw anything and if it crashes, so be it attitude.

However, if you don't want to spend $40 on this, delay the upgrade to Mountain Lion and just buy the latest iPhoto (if needed). At that point you can call Apple support since you recently purchased iPhoto (or possible recently purchased Lion) and ask AppleCare to verify your camera model is compatible with your software versions. You get 90 days of complimentary software support anytime you purchase Apple hardware or software since they want you to get up and running with your new purchase.