Nice work mate, but some thin clear plastic first, then your cover on top should keep most dust issues away
otherwise every time you lift and place back the material on its own, some fine dust gets around
Stitch some clear plastic lining on the inside of the cover and you're set
FWIW I use an open carton box as a cover, and I can put light stuff on top when the DSO isn't being used,
it's fast, keeps nasties out and the DSO can breath too
Hey, welcome to the forum