I'm noticing the stars in corners of my images being distorted. See here:
http://piggo.com/~troy/photos/2009/2009_02_28/m42.jpg or
http://piggo.com/~troy/photos/2009/2009_02_28/m83.jpg
I understand this is due to the optics of my scope, ED80 Pro. A focal reducer or field flattener (same thing?) will stop this? But this will change the field of view? How much? I see there are .6x etc. Is that directly proportional to the size of field of view?
Is there another way to prevent this distortion, other than post-processing?
Sorry for all the questions.