Several photographers have found a bug in the final Lightroom 2.5 and Camera Raw 5.5 releases that affects customers who are currently using a Mac computer with a PowerPC processor. The bug, introduced with our recent demosaic change to address sensors with unequal green response, affects raw files from Sony, Olympus, Panasonic and various medium format digital camera backs. The bug has the potential to create artifacts in the highlight area while using the highlight recovery tool. An example has been posted to Flickr here. (http://www.flickr.com/photos/carnivillain/3938260239/)
We apologize for the inconvenience but recommend that customers who have PowerPC hardware and process raw files from those manufacturers uninstall Lightroom 2.5 or Camera Raw 5.5 and install Lightroom 2.4 or Camera Raw 5.4. (Camera Raw 5.5 can be uninstalled by deleting the existing plug-in from the directory indicated in the Manual Installation instructions )
Customers converting their proprietary raw formats from Sony, Olympus, Panasonic and various medium format digital cameras should also not use the DNG Converter 5.5 with the compatibility setting lower than “Camera Raw 5.4 and later.” Again, we apologize for this inconvenience while we prepare a new update.
*Update(5:30PM PT, 9/26): Comments are not currently available on the Lightroom Journal so please comment in the Camera Raw Discussion Forum or the Lightroom Discussion Forum.