Coma in images

[Celestron4]

I have taken some images of NGC 281 Pacman Nebula and have come across some substantial coma around the edges of the image. I am currently using a Celestron Nexstar Evolution 6 SCT telescope on a Celestron AVX mount. I have an f6.3 focal reducer (again the Celestron one) and my main camera is a Canon EOS 1100D DSLR. I have had varying advice from using a camera with a smaller sensor to changing the telescope itself. What is my best option to deal with the issue without having to spend large amounts of money? I have attached the image if this helps.

Edited August 6, 2020 by Celestron4

[michael8554]

Thought we'd done this one to death in your other post......

Cheapest - crop the image.

Slightly more expense - add a few more millimetres of spacing between the camera and FR.

Michael