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Thread: Non-typical Secondary mirror on 20" RC?

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    Default Re: Non-typical Secondary mirror on 20" RC?



    Quote Originally Posted by smeyer8015 View Post
    I see, they temporarily unmounted the secondary.... I missed that.


    Scott
    Yes that mirror with the hole and tube in it is the primary, not the secondary.
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    Default Re: Non-typical Secondary mirror on 20" RC?

    Quote Originally Posted by CamelHat View Post
    After some searching I found that the auxiliary scope used for collimation is probably the "Takahashi collimating scope", basically a glorified Cheshire with magnification (apparently working quite well according to some reviews).

    So, the collimation procedure is really no different than that of my little AT6RC. That means that you first collimate the secondary using the small screws. If you are really good at collimating RCs you can attempt to collimate the primary, though my manual recommends to stay away from it and send it in for repair in that case.

    The protrusion on the secondary should not get in the way, I think. What may have happened is that someone tried to collimate the primary and failed, and because nobody was experienced enough to fix it, one could never successfully collimate the secondary afterwards.

    OP if you are still there please let us know if this could be the case.
    Well that makes much more sense than the impression I collected from the OP that they were testing/collimating the larger RC with a smaller Tak refractor.

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