I have been working on some old photos (Canon 10D RAW files) and when I open the files in Photoshop I find that the file has severe chromatic aberration (introduced upon opening). While in ACR, the file is fine (no CA) but when it opens in PS there are significant green and red shifts (unfixable using the lens correction filter). This happens regardless of whether I open the file as a smart object, a 16 bit or 8 bit file. I have recently loaded OSX 10.5.1, and the PS version is 10.0.1. Has anyone else had this problem?
You may need to zoom into the corners of the image to 200-400% to see and correct CA as well as other fringing. The Lens correction DOES produce reduced or eliminated defringing if you properly use it. If you have a question, post the raw file.