[glend (Glen)]

I have a 10" imaging newt build just completing and have run into one minor concern (at least I think it's minor but would like some opinions).

A bit of background: It's an open strut tube newt using carbon fibre longitudinal struts with marine ply frame members. It was assembled on a jig with a laser reference on each frame member and the tubes to keep it all in perfect alignment. I did a star test, and imaging test when I first assembled it (prior to final finish) and everything was great.

Now after final finish I have reassembled the components (mirror placement, focuser, guidescope mount, finder mount, etc) and re-collimated everthing. In checking all my measurements (made at the time of the initial test) I found that the secondary four vane spider was not perfectly equal in length in their vane brackets. They are only out by 2.5 mils on one of the four axis, and 1 mil on another.

This is am imaging scope so it has a slightly larger secondary than perhaps a normal visual newt (@ 63mm), and it's in perfect collimation as is.

So the question is, how obsessive do I need to be about the secondary centering when the 'possible' off centre position is out by such a small amount, and my image subs are great with no fall off on the sides.

If I move the secondary I will need to go through the whole collimation again - for what gain? I am tempted to leave it until I have to re-collimate for some reason.

What's the consensus?