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Old 06-09-2008, 04:47 PM
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Terry B
Country living & viewing

Terry B is offline
 
Join Date: Mar 2006
Location: Armidale
Posts: 2,789
Quote:
Originally Posted by Karls48 View Post
I have stupid question. How do you imagine close binaries? I can just split Alpha Centauri binary visually with 25mm eyepiece and 120mm refractor but with CCD camera (even it equals about 7mm eyepiece magnification) image comes up as one star. I know it is due to Airy disk size and that the eye got "smaller pixel" size. Anyone knows the formula how to calculate lowest angular resolution for given pixel size of CCD and telescope focal lenght? I have searched Web for split image of Alpha Centauri and I found only one image and it was taken in infrared.
The problem with Alpha cent is that it is very bright. It saturates very quickly.
I agree that I get it as 1 star with a 1 sec exposure but can image much closer mag 13 stars and detect the separation.
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