I am having trouble with my Rokinon 24mm + Canon 80D--the stars always look distorted. I am pretty sure it isn't because of drift or the mount because the distortion is the same size regardless of exposure length.
The pictures here are the bottom right and bottom left corners of a 30s exposure. It seems like the tails point towards the center of the image, which would suggest coma, right?
And I am pretty much screwed if it is coma, right? There's no fix?