Odd Star shapes - what causes this?

I am not sure how to diagnose this problem - I am using a Canon 20Da and 300MM f4 IS lens on a Kenko Sky Memo.

I am getting odd shaped stars with this combination - almost looks like a scope out of collimation. I don't think it is a tracking problem- but does it look like flexure, atmospheric problems (weather has been pretty bad lately), the lens itself? I think I have good polar alignment and it doesn't look like tracking problems I have seen before.

This is a 2 minute exposure.

BTW - I don't mean the diffraction spikes on the large star, I mean the slight "ghost" images or reflections on the other small stars...

Thanks in advance!

Attached Image:

Hello Gary, do you have a filter in front of your lens (e.g. UV filter)? If so, try again without it! That is quite a common cause.
Good luck,
Ivan