Adobe has highlighted a bug discovered in the latest Photoshop Lightroom and Camera Raw updates that may hit Mac PowerPC users.

Lightroom/Camera Raw product manager Tom Hogarty has posted information on the Lightroom Journal blog regarding the problem.

"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," writes Hogarty.

Several photographers have discovered the bug in the latest Lightroom 2.5 and Camera Raw 5.5 releases.

"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."

Hogarty apologises for the problem and recommends users 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 apologise for this inconvenience while we prepare a new update."