Self-guided

Discussion in 'General' started by Tom, May 23, 2016.

  1. Tom

    Tom Standard User

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    What makes an SBIG camera self-guided? I'm being told that it refers to the number of mirrors in the optical pathway of the guider relative to the main sensor. If the number of mirrors is odd it's not self-guided. If zero or even number of mirrors, it's self-guided. Is this true? If so, why is the FW8G-STXL referred to in your literature as self-guided when there's a mirror in the guider's optical path? I'm confused. Please advise.
    Tom
     
  2. Doug

    Doug Staff Member

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    Self-guiding means the system has a built-in autoguider camera.

    It used to be that most SBIG cameras had a guide chip in the main camera; these days only the STX still does. We've been moving the
    guide sensors into the filter wheel, so that it is in front of the filters.
     
  3. Craig Smith

    Craig Smith Standard User

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    Tom,

    From a practical perspective, especially regarding your image control software, "self-guiding" might refer to the number of cables coming from the camera... one vs two.

    Or, put another way, all of the output from the camera, both guiding and images, comes down the same pipeline. Your control software has to be able to handle that.

    Best regards,
    Craig Smith
     
  4. Tom

    Tom Standard User

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    Thanks for the reply. Both chips are controlled by the same driver, right? In Maxim DL self-guided camera would be set up as dual chip. But in both the original STL11000 (dual chip internal) and the FWG8-STXL (dual chip external remote), there is a pickoff mirror between the incident light and the guide chip. Does the self-guided camera electronically convert the resulting mirror image of the guide chip so that its orientation is the same as the main imaging chip?
     
  5. Doug

    Doug Staff Member

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    MaxIm DL can flip the image if you want it to. But you don't need to - the software figures out which direction is what during the calibration cycle.
     
  6. Tom

    Tom Standard User

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    So, as in the case of the older STL11000, the FW8G-STXL analog guide sensor signal is sent through the same multiplexer as the STXL11002 main sensor before passing to the AD converter?
     
  7. Doug

    Doug Staff Member

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    Actually it has a separate converter.
     
  8. Craig Smith

    Craig Smith Standard User

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    Tom,

    I was referring to the external USB interface in my comment.

    Best regards,
    Craig
     

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