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The Mekon
14-02-2016, 05:32 PM
I have suggested to a member here to use an off axis mask on his large reflector in the early evenings, when the seeing can be unsteady and a smaller aperture can be more useful.
Tried to pm some photos without result, hence this post.

Despite what many other commentators have said, I find my mask veru useful in resolving double stars clearly, which at full aperture can appear as bright blobs. The other night I had the mask on and the definition and clarity of the E & F stars in the trapezium were outstanding. Without the mask the C star tended to burn out the F and the separation was not as distinct.

As I have said before, this mask is so good for most doubles that I sold my AP 130EDT - I have a 7" F11 premium Apochromatic refractor inside my 18" SDM

Bombardon
14-02-2016, 05:38 PM
Many thanks, John. I get the idea now and I think I can make the adaptations to my open metal tube to take the mask. I will in due course let you know the results.
I appreciate your effort and helpful suggestions. Eugene