Alejandro Navarro avatar
Good evening everyone from Chile.

I'm going crazy. 
I've painted almost everything in my OTA, covered and protected every possible site where light could enter to the mirrors, and I'm still getting this "parasite ligths"
So I was wandering... are parasite lights actually? 

This is just a 10minutes image. I was testing backfocus, collimation, and light leaks. 
Back focus was pretty fine. 
Collimation It's getting better
But those lights or reflexions in the image.... don't know really.

Any help would be very appreciated. 

OTA: Skywatcher 1150p Quattro with coma corrector 0.865x F3.43.
Asi 294mcpro
Lpro (I've also tested it with L-enhance, and similar result)

Clear skies!!! 
Oskari Nikkinen avatar
That's an out of field diffraction spike from Alnilam based on the location. I'm not familiar with the term parasite light, but i think that's what you meant here?

There might not actually be a way to get rid of that if its perfectly placed just right outside the camera field of view like i think has happened here. I've had to deal with a few of these with my 8'' newtonian, but thankfully they are easy to get rid of in Photoshop (using lasso tool and content aware fill - poof - the rogue diffraction spike is gone).
Helpful
Alejandro Navarro avatar
I have this kind of lights in other images too.
and yes, Photoshop is there only solution, but I don't like that.
Thanks, I will look for what you said
Best regards!
Papa Brummbär avatar
Hallo do you use an OAG?
br and cs
Hampo
Alejandro Navarro avatar
No I don't.
I found the problem anyway. It was some reflections in the vanes.
They were too bright (my OTA is F4 and works at F3.4 with the reducer) 
So I painted the vanes, and the problem was solved.
I'm gonna change the spider too

greets!
Papa Brummbär avatar
OK, top job, I had such a problem with the OAG, because the astroproducts are not really lightproofed.
br and cs
Hampo
Alejandro Navarro avatar
Yes
I can't understand how these companies, knowing the issues, don't make products fully protected against light leaks or reflections
Cs
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