thank you for your reply. Since I am processing Fuji RAF files, I use capture one. I dont think it does layers well.
Capture One offers Adjustment layers e.g. for Exposure, Clarity, White Balance, Color Balance, and what have you, but I'm not clear on what causes the artifacts you mentioned. If they are Sharpening related, you can use a TIFF Export recipe which has C1 sharpening disabled.
So My workflow would have to be C1 pro for raw conversion cropping, culling, export to tiff in prophoto rgb-> adobe PS for capture sharpening and exposure adjustments-> AI clear then AI gigapixel for upscaling -> back to adobe PS for exposure, curves, clarity, temp adjustments, creative sharpening, etc -> export to final tiff.
You can then try to either add Capture Sharpening on a layer in PS, and save that as the basis for Gigapixel AI, or you could even try to skip Capture Sharpening and see how for Gigapixel AI can take you as it adds more detail than is in the source file. Then you only need to see if the upscaled result can be further improved by some additional processing.
I have found that Gigapixel AI can add so much credible detail to a file, that one can wonder if the additional steps before upscaling really add much to the upscaled result. I know that when I'm very careful, I can improve the source file to be used by Gigapixel by tweaking the sharpening locally, but it may be hard to see the effect of that in the final printed output.
So, a sanity check won't hurt, because Gigapixel is a gamechanger as far as my workflow is concerned.
Cheers,
Bart