Hey all, I apologize I pretty much forgot about this thread. I've been withholding a wealth of information about this filter wheel.
First of all, I purchased the OGMA 7x36mm filter wheel, which is actually a rebranded Touptek filter wheel. Initial impressions were very good, the build quality of the filter wheel seemed top notch, if not better than my QHY filter wheel. The board was clean, there were no visible opportunities for light leak on the external edges of the filter wheel.
There was however one isssue, but I must state ahead of time, this issue is not isolated to Touptek and can happen to any 36mm/APSC combo.
***NOTE: Reflective inside edges against the filterss***
**Notice reflections on the left corners**Here is the exact framing showing Propus and another local star being the culprits of reflection.
Basically, what was happening was I would get edge reflections from out of frame stars. I was using the provided filter masks, which are very sturdy and fit well, btw. It took me a couple weeks to isolate it down, but ultimately the coating/finish on the filter masks was too reflective. If a star was to land on the interior edge of the surface, it would reflect across the surface of the filter like a streak. This became a serious issue during my 20 minute exposures in narrowband, but was far less prevalent in broadband. You may not notice it until you stack all your images.
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Looking down the OTA. You can clearly see the interior edge of the filter mask reflecting against the filter. *note this sensor has since been replaced* ***
The solution, however was quite simple. I picked up some cheap blackout paint from Amazon, and painted each filter mask entirely. Once I got a solid two coats on the masks, I shined a flashlight and it was clear there was no opportunity for reflections anymore. Now, lemme preface one thing, this paint I used it water based, so I cannot in good faith recommend it... more of a 'use at your own risk' because I do not know what should happen if moisture were to build up inside. So far, I've had zero issues though. A couple friends have also now used this paint on their filter masks and alleviated issues as well. I do not believe they were aware of how reflective even 3D printed masks could be in their equipment. (Put this little tidbit of knowledge in your back pocket next time you're chasing reflections and light leaks).
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Water based paint, use at your own risk or find alternative**
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Zero chance of reflections now ***
I've been running the Touptek/OGMA filter wheel now for roughly 3 months without ANY further issues. 100% happy camper. Also, for those who may ask, I do not have unidirectional movement checked in the ASCOM settings.
