best method for dust busting and removing hairs is with the clone stamp tool. set opasity and flow to 100 duration constant and use a time shift of either 2 or neg 2 that way when you clone you won’t get repeating grain. very important or you will see hits of still grain never clone from the same frame or the one next to it. then just shift the offset till the frame lines up it will go from blurry to sharp when aligned. once lined up paint away with a soft edged brush. The clone source overlay is a little weird in afx if you can try combustion, the paint operator is great. hope this helps