I recently spent some more time working on a longer term project to digitize a large number of 35mm color slides (a mixture of Agfacolor and Kodachrome) that were taken back in 1971. Aside from some deterioration of the emulsion on some of the slides, and some fairly nasty color casts, one of the issues was surface dust, and because of the very delicate state of the emulsion I was reluctant to do much in the way of mechanical cleaning.
Fortunately the Canoscan 8400F I did the scanning with has Level 3 FARE infrared cleaning technology (similar to Digital ICE technology). The Canon supplied scanner software of course no longer works on Windows 10 Pro 64 bit, so I use it with VueScan, which also handles the infrared function for that scanner. That removed most of the light dust. The more serious spots I removed manually with the “inpaint” tool in Affinity photo. I did straightening and cropping in Affinity Photo.
I used Studio 1 as a plug in from Affinity Photo. (Sorry Topaz but I personally prefer it to Studio 2). I specifically used Studio 1->AI Clear, which I have found often gives me a better result than the free standing AI Sharpen->AI Clear. Whilst in Studio 1, I did a lot of the basic tweaks and color corrections. I used LAB sharpening in Affinity Photo for the final sharpen.
Not perfect, but reasonably happy with the results so far.
The screen shot below is from a “recovered” 49 year old Agfacolor slide.