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Coma issues & fingerprints on filters
Hi all,
Last night I set up my rig with the hope of using my asi294mc for the first time on Thor's Helmet. The camera did not disappoint, more nebulosity appeared in the stretched preview than I could have dreamed of with my DSLR! My previous egg-shaped stars issue fixed itself, so I am assuming it was due to poor polar alignment or tilt. Either way, glad that issue disappeared.
However, one issue persisted: coma. The coma is terrible and I took hours trying to fix it. I never got past rotating the image for Thor's Helmet. I tried so many different configurations. Below is the exact setup I used (not my photo though):
L-Extreme filter -> Baader MPCC III -> 16.5mm -> 21mm -> ASI294mc
As you can see on the two images below which I took, I don't think we're talking a millimetre or two of spacers. Is it possible that coma has been over-corrected? Or would coma appear perpendicularly if that were the case? I experimented for hours and gave up. Thanks for helping.
I also accidentally touched the L-Extreme filter and Baader MPCC with my fingers a couple of times. Any tips on cleaning filters would also be much appreciated.
Clear skies,
Stéphane
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