I finally got a clear sky with minimal wind and I took my first sub last night from the lagoon nebula. The sub can be accessed here: https://drive.google...iew?usp=sharing
As you can see, I think I got a lot of coma specially when looking toward the bottom left corner. I use a Explore Scientific 80mm telescope and I use a 2" Explore Scientific field flattener with a 55mm back focus (I made sure the back focus is at 55mm +/- 1mm). Still, it seems I got a lot of coma with my stars. I doubt that it would be due to bad tracking and autoguiding because the stars at the center look better. Does anyone know why I might be getting such a large coma effect and how to deal with it? Thanks!
Edit: I took this image using ZWO 1.25" Ha filter.
Edit2: I use off axis guiding. I made sure the prism is not blocking the sensor even a bit.
Edited by salehest6990, 25 June 2019 - 05:53 PM.