I'm on a quest to resolve a problem with my second monitor when using Photoshop. When I hit F in photoshop to toggle between display modes or when I zoom in or out this happens:
Ok, well it's turned sideways but you get the point. Up until pretty recently I was using OSX 10.6.8 with Photoshop CS4 with no issues but was running into some problems with apps etc. so I upgraded to Yosemite. Thats when the problem started. In an effort to solve this I did a clean install of Mavericks in the hopes that Yosemite was too new and hadn't gotten the bugs worked out. I then re-installed CS4 and it no longer has this problem but another equally annoying problem; the profile for the 2nd monitor looks so desaturated and terrible that I can't use it to retouch despite several attempts at new calibration.
Out of curiosity I tried the Photoshop CC trial to see if the mosaic problem was fixed but it wasn't. The color now looked right but the mosaic problem persists. Here is info on my computer:
I've changed in System Preferences>Energy Saver>Graphics to Higher Quality but nothing changed. In Photoshop I tried Preferences>Performance>Graphics Processor Settings>Advanced Settings>Drawing changed to Basic and that didn't resolve the problem either. Any ideas?
MacOS 10.10 still has a number of video driver bugs, some causing display corruption and others causing crashes.
Apple is aware of these driver problems and working on solutions.
Turning off Photoshop's GPU usage may help.
But if you need the GPU features, you may want to downgrade to a stable version of MacOS.
Thank you, that was the key. I was so close. Turning off the Graphics Processor in Preferences>Performance did the trick. What a relief.
As it turned out this solved the problem in Photoshop CC but I was still having color profile problems in CS4 so I'm just going to make the switch over to CC(about time right?).