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Thanks for the feedback guys. I recently brought the scope from my home country and in my hurry to install it I didn't clean it properly. I dismantled it during the weekend and gave it a good mirror cleanup as well as fiddled a bit with the collimation which was a bit off, but can't tell for sure as my chesire moves in the focuser quite a bit and does not produce repetable results.
As I will have a trip to Syd I was thinking of buying an MPCC and a Hotech collimator but then changed my mind and I'll try to collimate on a star with the entire imaging train in position. There's no point in collimating and then installing the flip mirror and camera.
I blame it on collimation as previous pictures taken 3 years ago had coma but they were better than the present one. Attached are two examples. M42 is from a while back and although coma is visible, on the other NGC 3293, the lower right corner is defocused and upper left has "seagull" shaped stars. Another strange thing that I blame on an optical problem is that although I had very good focus, some of the stars have double difraction spikes (ie. the blue one to the right of the galaxy in the original picture).
I ordered a set of Bob's Knobs and I'll see where this takes me together with the MPCC.
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