Lately, I have found a few old photos that were ‘hand retouched’ at some stage. That is, painted over with ink or paint on top of the photo to try to fix imperfections.
Obviously these would have been done some time ago – before electronic photo restoration – and usually are faded a bit as well. But for me the biggest problem is the matt paint versus the gloss photo paper that makes my restoration tools less effective.
I find I must use electronic ‘painting’ rather than automatic means!
And that is time consuming. And adds to the cost.

But the results can be fantastic! See below.