Focal reducer and ao8 sc2 back focus

Discussion in 'Guiding and Adaptive Optics - StarChaser and AO' started by vinifera, Sep 18, 2020.

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  1. vinifera

    vinifera Cyanogen Customer

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    I am experimenting with a focal reducer (Meade 6.3) that fits well into my image train - Meade SCT - Meade 6.3 -AO8- SC2-Fw5–STF8300M.

    I can get the 8300 at the exact back focus of the reducer but the travel of the sc2 - and being at a shorter distance to the FR in front of the fw5 and camera - won’t reach focus, ie can’t seem to get to the same back focus distance.

    could manually do it when I had an st-i.

    tricks or thoughts?
     
    vinifera, Sep 18, 2020
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  2. vinifera

    vinifera Cyanogen Customer

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    So it's partly a focus issue and partly that the pickoff mirror isn't really seen in the image circle of the FR. I've included a photo of the setup. The focus on the STF8300 is spot on, even indoors at 45 feet from the scope.

    Thoughts on how to open up the field (other than remove the FR?)
     

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    vinifera, Sep 21, 2020
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  3. Colin Haig

    Colin Haig Staff Member

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    What Meade scope is that FR on?

    Here's a suggestion:
    Aiming 45 feet away is not going to work.
    Point the telescope at the moon. Get the camera in focus.
    Adjust the pick off mirror so that you can get part of the moon on the guide sensor.
    Adjust the pick off mirror focus.
     
    Colin Haig, Sep 22, 2020
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