From: "Tom Krajci" 
To: , 
Reply-To: "Tom Krajci" 


>From: "Jack Schmidling" 

>My first question is:  Are they all like this or is this some Orion
>"innovation"?

Mostly like that, but some newer ones have holographically generated
patterns...concentric rings, cross hairs, etc. in addition to the center
spot.

>Assuming they are all like this, how is it possible to align things
when
>looking off axis with the diagonal blocking an on axis view.

You can view the reflection of the laser collimator's face (shoved in the
focuser tube) by looking at the main mirror, or you can use a handheld
mirror to 'peek' around the secondary if the secondary blocks your view.

>It is obvious that this thing is no better than the care that went into
>aligning the laser and this could be all over the place.

Put the collimator in a V block and rotate it, and see if the laser spot
'wanders' on a distant wall...you can test how well aligned the beam is
with the mechanical axis of the barrel...to about an arcminute or two.

>I find it interesting that when I adjust the diagonal with a sight tube
and
>peephole and then insert the laser, dot is never on the center of the
>mirror.  This either says it is more accurate than the somewhat
subjective
>eyeball method or
>something else that is not good.

See:
http://zebu.uoregon.edu/~mbartels/kolli/kolli.html
it talks about laser collimators and other approaches.

I hope this helps.

Tom Krajci
Tashkent, Uzbekistan


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