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    Default N208CF collimation question



    Hi,

    I've had a bit of an adventure with my ES 8" reflector and the secondary mirror. I've had to replace the secondary assembly once since purchasing the scope last fall. ES has made some design changes to improve the secondary, but hasn't kept the documentation up to date on the collimation process. The ES tech support has been very responsive, but I still am questioning how I'm collimating the scope. The latest secondary has both allen wrench screws (3) and knobs (3). I've been loosing the allen screws slightly and then using the knobs to perform the alignment, then tightening up the allen screws to "lock down" the alignment. This is opposite of what ES tech support recommended. However, using the allen screws for the alignment adjustment didn't make sense to me when I have the knobs there. The first secondary assembly I had would not keep alignment; even slewing the scope a couple times would put it out of alignment. Finally it would not collimate as one of the screws broke. The replacement is working at the moment, but I don't won't to get into the same situation as the first secondary .

    Any thoughts, suggestions?

    Thanks!
    Brian
    Equipment: Explore Scientific N208CF(f/3.9), Ioptron ALT AZ Pro, ASI 294 Cmos camera, Orion G3 CCD camera,Celestron SLT130.

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    Default Re: N208CF collimation question

    I have the 208CF as well and also found that the best/only way to collimate the secondary is just as you've discovered-ie- using the knobs for alignment and the setscrews for securing the setting

 

 

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