For the background, I am often using self adhesive velvet sheets, sold in rolls of about 50cm width in various colours (black, dark green, dark red, Brown, grey) found in art material shops.
As I expose the frames in competition without protective glass, I just clean the flat with a very soft butterfl brush and for the background a toothbrush, and a good air blow ...
Then on pictures, I mak the here ad there spots which cold be there to the pixel with a software. ours took less than 3 miutes to be cleaned-up and reformatted.