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Old 26-08-2013, 04:27 PM
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Lee
Colour is over-rated

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Join Date: Sep 2005
Location: Newcastle, Australia
Posts: 2,414
Question about OAG focusing

My TSOAG9 arrived today... problem is my lodestar is sequestered away until father's day...
So I'm preparing, hoping for a hassle-free-first-light, if such a thing exists...

I'm trying to come to grips with focusing.

The chip in my CCD is approximately 45mm out from the plane of the OAG prism. Does this mean, that, field curvature aside, the CCD in the lodestar needs to be approx 45mm from the prism in the OAG?

And on the same line, once the guide cam is focused, moving the whole guide-cam-prism-stalk in and out shouldn't appreciably affect the focus at the guide cam CCD? Or will it??
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