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Old 30-01-2021, 12:03 AM
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Camelopardalis (Dunk)
Drifting from the pole

Camelopardalis is offline
 
Join Date: Feb 2013
Location: Brisbane
Posts: 5,433
Quote:
Originally Posted by lazjen View Post
If I understand the diagram with the reducer, it still should be ok at full frame camera?
I guess it depends on your definition of OK

With the reducer, the spot size increases from 3.8um in the centre to 8.7um at 21mm off-axis, and they’re not round. You prolly wouldn’t see that with something like a 6D with large(ish) pixels and a CFA. With a mono ASI6200/QHY600 you might. Assuming good conditions when the atmosphere isn’t smearing the shape of the stars anyhow

The 1x flattener keeps the stars tighter, and with almost no vignetting...
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