There have been some discussions around seeing and how it can affect the clarity of images so I thought this would be a nice illustration of what can happen if your seeing is bad even at medium focal lengths.
Both images taken with Starfire 152 EDF at F7.5 using Starlightxpress SXVH9 CCD, same site (Canberra ACT 780m ASL), same photographer, same mount, with only basic processing and esposure times were similar too, plus careful attention to focus was used (the imager is anal about this) in both cases.
Image on the Left was taken in very poor seeing
Image on the right was taken in quite good seeing
Even at the relatively modest focal length of 1140mm - the difference is remarkable!
Here is the comparison
So seeing is
everything (as is focus) as far as I am concerned, here in Newcastle the left hand image is easy to take most nights but the right hand image is a rarity indeed (if ever)
Mike