fuzzy spider

I enjoyed the discussion about the razor blade spider vanes. (Maybe my next project, he he.) So apparently it doesn't matter how thin they get, they will still cause those spikes. Maybe it has something to do with the smoothness of the surface. (?)

Has anyone tried making a fuzzy spider? I am thinking - what about covering the thing in felt or some kind of flocking material? Sure they would be thicker, but if the surface is rough enough you might get the desired reduction in spikes.

Before I run out to try this, has anyone done it already? What do y'all think?

Charlie

You are right. To repeat; A. Danjon believed that as the vanes cooled off they became surrounded by a layer of warm air that creates the spikes by refraction (rather than diffraction) and his colleague A. Couder eliminated them by covering the vanes with polished aluminum (S&T April 1978, page 354 in Gleanings for ATM's article Star Images in the Presence of Aberrations). My curved vanes are of aluminum and not painted. John Westfall, then director of the ALPO, praised this scopes' quality. Ron