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Old 06-06-2008, 03:50 PM
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allan gould
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allan gould is offline
 
Join Date: May 2005
Location: Brisbane
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Quote:
Originally Posted by §AB View Post
generally, the longer the focal length of your scope, the bigger the mag difference is between any 2 given eyepiece F/Ls.

for example:

on a 600mm FL scope, the 5 and 8mm produce 120x and 75x respectively (diff = 45x) ,

on a 1250mm FL scope, the values are 250x and 156x (diff = 94x).

on a 2000mm FL scope, the values are 400x and 250x (diff = 150x).

overall the difference between 5 and 8mm is significant enough at all focal lengths to warrant having both.
Thanks for that. I'm seriously thinking of both the 5mm and 17mm to complete my collection
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