In my personal experience Photo AI works best on images shot digitally rather than scanned analogue images. I would like to see an AI model that is specifically made for Analogue film, slides and prints. This would allow for sharpening that can improve slightly blurry images and not sharpen the grain. Also denoising that can remove excessive grain. I find that I often have to use the old fashioned denoise tools before the advent of AI. They seem to do a much better job of denoising analogue images. Denoising with AI does not appear to be so effective.
Kind regards
Chris
