Re: [APML] Re: IC 2948 image

["Shekhar Borde" <shekhar@prodigy.net>]

> Actually, my scope is probably closer to f/4.3, since I masked off the
> outer 4 mm of the primary mirror (following a suggestion on this list a
> few years ago). These scopes often suffer from a turned down edge,
> resulting in diffuse halos around bright stars with the retaining clips
> visible as dark bands - as, for example, in this 6-year-old M42 image:
> 

This is very true.  My scope also had a TDE and I had to mask off the
edge.  The images have improved considerably since (in spite of my 
technique :-))

Here is another early image that shows this problem:

http://www.rawbw.com/~shekhar/m45.html


Shekhar




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