Well, i do a sort of wet gate with diffuse light too. To me diffuse light helps with my sysyem since i have tested collimated light with worse achievement . I soak the film with vaseline oil then pass trough mechanical cleaning system. This way dust and dirt are removed and the film remains wet. Finally i scan the film emulsion for the highest quality. I can scan from sd to 2.5k to image sequence. This system works best with reversal, with negative film the difference is not noticeable aside dust and dirt removed.
Here a brief description. (hem , the voice is robot,sorry for some weird pronunciation)