[mr.sneezy (Martin)]

I have made a combination collimation eyepiece and setup my reflector scope as best as possible for the first go at it. I get a nice round star diffraction pattern in the center of the view now (it was rubbish when I first unpacked and tried out the scope).
What I have noticed now that I bought a better eye piece, is that the pattern skews right as I shift the object to the left of center, but it still looks round when off center to the right.
Would that imply the focuser tube is not square to the main tube and main mirror ? Or can it be something else too ?
Martin