Photoshop problem with Mac

[dario25032856aa0d]

When I'm working on an CYMK file and I zoom in and out or move the window a strange effects occurs.

As you can see in the attached screensot.

If I turn my file into an RGB file the effects disppear. 

Any idea of what's going on??

Thanks

 

[Kevin Stohlmeyer]

What version of Photoshop CC 2020 are you running? What Mac Os?

If you can, go to Help>System Info and copy/paste the details in here.

This looks to be a previously logged issue with graphics cards that was resolved with newer versions of Photoshop.

[TheDigitalDog]

First, try disabling GPU in the Preferences (Performance tab). Any better?
You can try this too: in Preferences>Technology Previews, check the box 'Deactivate Native Canvas' and uncheck 'Enable Native Canvas Rulers' options, then restart Photoshop. Does this work?
If not, recalibrate and build a new ICC display profile, the old one might be corrupted.
If you are using software/hardware for this task, be sure the software is set to build a matrix not LUT profile, Version 2 not Version 4 profile.

If turning OFF GPU works, it's a GPU bug and you need to contact the manufacturer or find out if there's an updated driver for it. On the Mac, that's part of the OS update(s) so if this is the latest OS version, you may need to roll back a release.
Also see: https://helpx.adobe.com/photoshop/kb/acr-gpu-faq.html