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Old 20-03-2012, 07:35 AM
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cybereye (Mario)
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cybereye is offline
 
Join Date: Aug 2009
Location: Brisbane
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A question on eyepiece projection & resolution

Good morning!

I have a question on just how much resolution I can expect from my current planetary imaging setup. To set up the question, I'll firstly go through how I understand some of the basics.

I have an 8" reflector with a focal length of 1200mm. As I understand it, the maximum useful magnification I will get from my scope is 400x. Now using a 10mm eyepiece I have a magnification of 120x and if I add my 2x Barlow into the mix my magnification is now 240x which is still well below the theoretical 400x that I spoke about before.

However when I take an image using eyepiece projection onto the chip of my QHY5V, I calculate from my plate scale that I'm working my scope as though it has a focal length of about 6400mm. So my question is:

Does that mean my magnification is 640x and I've gone way past my theoretical limit of magnification for my scope? Or am I OK and I can use a 3x Barlow to give me more detail (this being 360x magnification)?

Obviously I haven't taken seeing into consideration but I'll keep that out of the equations for the time-being!!

Thanks in advance for any help people might be able to give me on this,

Cheers,
Mario
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