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Secondary mirror offset

Started by fblue, 07/16/2003 08:01PM
Posted 07/16/2003 08:01PM Opening Post
I am wondering if someone can answer a question about the secondary mirror offset.
I just got a new LaserMax collimator in today with holographic grid.
When I put the secondary shadow on a wall I see the mirror is offset away from the focuser. it is centered verticaly, it is only offset away from the focuser.
Is this due to the offet of the secondary mirror? I seem to be able to collimated fine with this offset. I am aware that usually there is an offset with the secondary, but have no idea of how mush or which direction is normal.
Thanks for your help.
Floyd

[SIZE="Large"][/SIZE][COLOR="Blue"][/COLOR] Floyd Blue grin
Amateur Imager
Posted 07/16/2003 10:59PM #1
Floyd,
I don't think this is the case. I would recommend adjusting the primary untill the shadow is centered in the grid. Assuming of course that you've already adjusted the secondary so that the laser hits the center of the primary.
Although written before the day of laser collimators, 'Newtonian Notes' says "There is no effect on collimation." in regards to secondary offset.
Hope this helps and clear skies to ya.
Bob

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