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RASA 8 star deformations - tilt, diffraction, over-exposure?

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#1 chimerasaurus

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Posted 25 November 2021 - 03:46 PM

When imaging with my RASA 8, bright stars show obvious signs of deformations. For example, here are stars from an image I took of M42.

 

Top right

M42 top right
 
Lower left
M42 lower left
 
I have tried adjusting gain, exposure time, and the camera being used; bright stars always produce those abnormalities. Could these be a form of diffraction spike? I am still using the fatty ZWO cable. I ran CCD Inspector and the frames didn't look horribly tilted (though I could be wrong.)
 
CCD Inspector

 

 

Does anyone have suggestions on what to chase to mitigate these super bright and malformed stars? Thanks!



#2 j21blackjack

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Posted 30 November 2021 - 10:39 PM

My stars look identical to yours, I want to blame my cables, but I'm starting to think that isn't the problem.

#3 galacticinsomnia

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Posted 01 December 2021 - 12:19 AM

I don't have a RASA, but.... looks like collimation judging from the surrounding stars.  Also doesn't look like you nailed the focus. 

Maybe something like this would help you...
https://telescopes.n...ron-8-rasa.html

 

Clear Skies !!



#4 bugbit

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Posted 01 December 2021 - 06:46 PM

Take a look at this thread.

https://www.cloudyni...i#entry11514279




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