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Old 01-07-2009, 09:42 PM
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wysiwyg (Mark)
Astrophotographer

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Join Date: Oct 2007
Location: Adelaide, Australia
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Quote:
Originally Posted by jase View Post

The primary reason why you rotate the imaging train post flip is to pick up the same guide star when guiding on axis. Rather important when you're operating at long focal lengths. For the regular imager, particularly one using a wide field instrument this is a mute point as guide stars are typically plentiful for on axis guiding. So in this case, you wouldn't bother rotating your imaging train.

Cheers
Jase,

You touched on an interesting point here. Even in widefield I would have thought that rotation after a flip is a must, especially if you are going to plate solve. I could be wrong, but how can you achive a plate solve with the image 180 degrees.
My understanding of plate solving is still very limited, so forgive me if I am missing something.

Mark
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