(solved) Odd stars, what's causing it? Collimation?

[Jannis]

So just got ready for a night with nice weather, and set up everything...

Then BAM! This is the stars i'm getting... :'(

Here's a frame in focus (I know it's in focuse (focus mask picture confirms)), and one out of focuse.  The issue is clearly there far out of focuse also.

Now last time i used the same scope, camera and equipment it was all fine - however i did wipe off the come corrector and have been mooving the scope around since last use. I'm sure i haven't bumped into it, dropped it, or touched any of the mirror screws though.

Should i recollimate, or might it be something else i'm overlooking?

 

[Tim]

Was the scope  cooled before imaging?

Are there any streaks or lines on the coma corrector?  Try removing the corrector and imaging a central star.

If the out of focus star image is of a centred star then your collimation is out a bit, but I shouldn't think enough to give that smearing. 

 

[Jannis]

Rechecked collimation now, appears to be pretty much spot on, but...

Um.. OMG, i just realized, just as you replied Tim.
I'm so used to having a permanent outdoor setup that i haven't had to think about cooldown time for the scope for years...

*puts everything back and rechecks* ...  *facepalm*
It was indeed the heat. It had only been out for ~30-40 min, clearly not enough. 

Thanks for the quick reply!