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Old 19-10-2008, 01:33 AM
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h0ughy (David)
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Join Date: Apr 2005
Location: NEWCASTLE NSW Australia
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Quote:
Originally Posted by redsquash View Post
HI David ,
I am responding to your PM on the forum , as other members may have a similar question.
How effective is this mask for fast minor , grab and go scopes ?
Are the effects similar for visual observations or is this predominately an exercise for astrophotogphy?

My newton specs are
130mm aperture
f/5
focal length 650mm
45mm or 35% central obstruction by secondary mirror

I tried doing the the calculations but there was a term or two which threw me so I just guessed the data.
Can you help with the claculation.
given the limitation of this scope is there going to be a noticeable difference
i will have a look when i get to work on Monday - have left the file on m PC there
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