Strange artifact in images with Askar 120 APO setup

Sky-Watcher EQ6-R Pro LRGB Artifacts Help Needed Troubleshooting
4 replies•184 views
Juan Pablo De la Cruz avatar
Juan Pablo De la Cruz avatar

Hi, I’m getting a strange artifact in my images — has anyone experienced something similar?

Setup:
– Askar 120 APO
– ZWO Filter Wheel
– Antlia V-Series LRGB filters
– ZWO OAG
– ASI2900MM
– SkyWatcher EQ6-R Pro

Any ideas on what might be causing it would be greatly appreciated.


Luminance Filter

Screenshot 2025-11-20 211632.jpgRed Filter
📷 image.pngimage.png

Noah Tingey avatar
Noah Tingey avatar

Looks a lot like the OAG prism is blocking your sensor. Loop exposures on a flat panel and adjust the depth of the OAG until its no longer darkening your FOV.

Helpful Concise
Alex Nicholas avatar
Alex Nicholas avatar

Thats your OAG pick off prism. Flats will correct it, but id be adjusting it so there is no shadow so flats are only correcting vignetting

Juan Pablo De la Cruz avatar
Juan Pablo De la Cruz avatar

Thanks, Noah and Alex! Tomorrow I’ll adjust the OAG. Sometimes I get overwhelmed and miss the obvious things.

Well written Respectful
Juan Pablo De la Cruz avatar
Juan Pablo De la Cruz avatar

Solved!!! Thaks for the help.

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