Keep your corrector dry but do not be obsessive about keeping dust off.
Dust causes almost no optical evils.
Even the big "dust particle" the central obstruction does not faze the optics.
But keep the scope and ALL the optics as dry as possible.
I just noticed that I have some tiny white spots on the corrector plate.
These white (or silver) spots are something to perhaps worry about since they represent contaminants from the atmosphere and which MAY degrade the coatings. :oops:
  