PhotoMono123 wrote:
Take a look at Pixelmator Pro (Apple App Store $25). It is an Apple-only program and it integrates nicely with Apple Photos. If you use the Adobe photo package, you can import a Photoshop or tiff file complete with layers.
Two very highly regarded free programs are DarkTable and RawTherapee.
My son just pulled up a YouTube on DarkTable a few minutes before I saw this post. He likes it and I might start using it too since there will now be someone else with experience that I can lean on.