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Old 13-07-2020, 03:10 PM
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Stonius (Markus)
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Quote:
Originally Posted by Merlin66 View Post
Wayne/ Bojan,
There's minimal or no coma in the SCT. That's what the corrector fixes.
Unfortunately you're left with some field curvature.
My checking of reducers has always (excuse the pun!) focused on the on-axis image - I use my SCT for spectroscopy only.
Baader issued a chart for checking reducer spacing, not for the reduction factor but the suppressing of aberrations.
This infers that if you're seeing what looks like coma at the edges, the the reducer spacing is too small.......

Could you explain a bit more about those images? As in how they're used? Or does it just show you what the aberrations look like across the field (for educational rather than diagnostic purposes)?


Cheers
Markus
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