PHOTOSHOP VERTION

If you look at the Photoshop System Requirements for Mac, currently the latest version (Photoshop 25) is supported on macOS 12. The current minimum requirement is macOS 11.

But you might also keep the big picture in mind. Both Apple and Adobe support the last three major versions of macOS. Every year, when Apple and Adobe do their major new releases, the system requirements ratchet up by one major version.

So in just a few months, if historical patterns hold, there is a good chance that when Apple releases macOS 15, both Apple and Adobe will drop support for macOS 11 so the minimum will become macOS 12.

The next year (2025), if Apple and Adobe advance to macOS 13 as the minimum, your macOS 12 iMac might no longer be able to install the newest version of Photoshop unless it’s possible to upgrade macOS on it.

Also  — you asked about running Photoshop “without problems.” That is not possible, there are always some problems even if you are 100% up to date with a new Mac. The question is actually about if the known problems are minor enough to not get in your way. You can always read about the current known issues in Photoshop at this link:

https://helpx.adobe.com/photoshop/kb/known-issues.html

The latest Photoshop version should run fine on macOS Monterey.

Although Adobe does recommend macOS Ventura or Sonoma for the best experience, it should still do

fine on your present OS.

It has more to do with the specs of your iMac as to how well Photoshop will run.