SkyWatcher Black Diamond MAK-180 collimation help

[flyingbaby (Allan Chan)]

Hi everyone,

I just did a star test on my Skywatcher MAK180 for collimation.

The attached are the star test results on both side of the focus.

Can someone please advice me by looking at the pictures, if my MAK's collimation is perfect? as I sometimes saw coma on the edge of the FOV when using Televue Ethos 13mm eyepieces on a diagonal.

Thanks

[Allan_L (Allan)]

Hi Allan,
I don't purport to be an expert, far from it.
But those images look as close to perfect as I have seen.
OK, there is a little bobble in the top left of the second one, but the rest of the image looks so good I would expect that, if anything, the slight deflection may be due to an external item. A mis-shaped dew shield caused a similar effect on one of my CPC1100 star tests, for example.

The "coma" may be an effect of optics not yet cooled to ambient, general poor atmospheric conditions in general, or even the image being slightly out of focus. I am not sure. But the collimation looks good to me.

Thats my vote. What do others think?