SC-2 pick-off mirror alignment question

Discussion in 'Guiding and Adaptive Optics - StarChaser and AO' started by John G., Nov 14, 2023.

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  1. John G.

    John G. Standard User

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    Now that I've got my new SC-2 OAG to connect, I am having some trouble finding stars and focusing. After trying some suggestions from Colin like using something bright like the Moon to focus on, I am still not able to see anything in the autoguider window. I am attaching an image of the positioning of the pick-off mirror to the CCD (Aluma 694CCD). Right now the mirror is all the way into the optical path. Does look right?

    John G.
     

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    John G., Nov 14, 2023
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  2. Doug

    Doug Staff Member

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    That photo makes it look like the mirror is not attached properly and is at an angle. Might be an illusion if the shot isn't perfectly straight... but can you verify?
     
    Doug, Nov 14, 2023
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  3. John G.

    John G. Standard User

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    I will attach two other images that might make the situation clearer.

    The camera is working, but shows nothing except light and dark areas regardless of what the telescope is pointing to.
     

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    John G., Nov 14, 2023
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  4. Doug

    Doug Staff Member

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    You may be very far out of focus - it takes quite a lot of turns to move the sensor position from one end to the other.

    You should be able to find the moon! Be aware that the pick-off mirror is offset from the main camera. Center the moon in the main camera, then try up/down/left/right until you get something very bright in the guider field. Then find the limb of the moon and focus on that.
     
    Doug, Nov 14, 2023
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  5. John G.

    John G. Standard User

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    I did try that. But I will attempt another try. So, you think the positioning of the mirror should allow me to see something?
     
    John G., Nov 14, 2023
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  6. Doug

    Doug Staff Member

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    For sure.
     
    Doug, Nov 14, 2023
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  7. John G.

    John G. Standard User

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    Doug:
    I will try on the Moon again as soon as it becomes visible. In the meantime, can you tell about how many total turns the focus adjustment has on the SC-2 so I can place the focus roughly in the middle the next time I try to focus on the Moon?
     
    John G., Nov 16, 2023
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