Quote:
Originally Posted by Peter Ward
CaK? Get one! Cheap as chips  |
For the ignorant among us (i.e. me), could you explain the use of a CaK filter? Is this another type of etalon used instead of the H-alpha one on a solar scope, or is it used in conjunction with a white-light full-aperture filter (such as Baader film), like a solar continuum filter?
EDIT I was assuming the former but the "cheap as chips" made me suspect the latter.
Cheers
Steffen.