Thx (Danka) to LeonieDF for pointing me at this discussion board.
I have exactly the same problems as Daniel. Common items I seem to have: iMAC, OS Lion, Canon Raw, H/W issue with my iMac (Daniel replaced whole computer, techies at Apple just replaced disk on mine after initial crash back in Nov shortly after migrating to Lion), there is no rhyme or reason for corruptions to occur and they happen randomly either on Master and/or Preview and/or download to desktop or to mail or within Aperture display itself.
Totally frustrating. Doesn't appear to be issue with camera, USB cable, memory cards or anything related as to how things are uploaded to Aperture from the capture medium.
Problems seemed to start after upgrade to Lion and subsequent hard drive failure/replacement by Apple. My suspicion is centered on interphase problems between video card (?) and Aperture itself while running on Lion.
Hate to lug the 27 inch iMAC to the Apple Store again but this time I have this thread to show them that I'm not the only one. Previously GeniusBar was useless even after seeing the corruption. Problem is in trying to find a consistent way to show this happening. Totally random!!! Some corrupted images actually might change during a session or switch-out between the Master and the Preview!
Thank you everyone for your suggestions in this discussion... but just as Daniel discovered none of the suggestions seemed to work out a solution. That's why
I am more and more leaning to the fact that this is a hardware or software interface problem within the MAC or MAC operating system if its not Aperture iteself.
Daniel,
did you have any success at the Apple store Genius Bar?