Re: ATM Collimation Question

["Jim Fly" <flyj@iol-12.net>]

>   5) Center the reflected laser beam so that it retraces the the same
>      path from primary to secondary to the laser source.  This is done
>      by adjusting the screws on the primary.


>The final collimation is against a centered star (polaris is best, since
>I don't yet have a tracker), which should show the secondary shadow
centered
>in the diffraction rings on both sides of focus.  If the shadow isn't
>centered (it should be close after the above procedure), then it's
direction
>from center gives an indication as to how to make the final adjustment.
>The final adjustment is made with the primary screws

Everything was great until at the end you relied on a visual
assessment/judgement of the shadow centered symmetry as the final primary
adjustment criteria to in effect "defeat" that wonderful precision of the
laser you used to set the primary in step 5.

Why?????

Regards,

Jim Fly
ATM Craftsman & Engineer
Huntsville, Al
flyj@iol-12.net

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