Resolved Guide Chip Focus SBIG 11002

Discussion in 'Image Capture' started by Marshall Edgell, Oct 22, 2017.

  1. Marshall Edgell

    Marshall Edgell Cyanogen Customer

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    I find it very difficult at best to get focus on the 11002 guide chip. Does anyone have a good algorithm for this?

    marshall
     
  2. Colin Haig

    Colin Haig Cyanogen Customer

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    Can you describe EXACTLY what camera you have (STL, STXL) and any optical hardware, filterwheel, focal reducer, anything else ?
    What software are you using? FocusMax, MaxIm, TSX CAO ?
     
  3. Marshall Edgell

    Marshall Edgell Cyanogen Customer

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    Colin

    I have an SBIG STXL 11002. No optical hardware or focal reducer. I have the SBIG FW8G-STXL with guide chip. I use MaximDL and CCDAutopilot. I use the Planewave autofocuser.

    The guide chip is supposed to be focused by a knob on the side of the filter wheel. I found it extremely difficult to get good focus.

    marshall

     
  4. Marshall Edgell

    Marshall Edgell Cyanogen Customer

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    Colin

    I have an SBIG STXL 11002. No optical hardware or focal reducer. I have the SBIG FW8G-STXL with guide chip. I use MaximDL and CCDAutopilot. I use the Planewave autofocuser.

    The guide chip is supposed to be focused by a knob on the side of the filter wheel. I found it extremely difficult to get good focus.

    marshall
     
  5. Doug

    Doug Staff Member

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    You should only have to ever set this once. Focus the main camera first. Then adjust the guide camera to achieve decent focus.

    The guide camera is significantly off-axis. Depending on the telescope you may not be able to get pristine images. Just find the best focus you can, and it will work for guiding.
     
  6. Marshall Edgell

    Marshall Edgell Cyanogen Customer

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    Doug

    I have a Planewave CDK 17 which is supposed to have excellent stars to the edge of the image so I was expecting excellent stars with the SBIG off-axis guide chip.

    marshall
     
  7. Doug

    Doug Staff Member

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    I'm sure it's pretty good, but no instrument is utterly free of aberration, and the focal reducer in the guide camera will tend to make it a little worse.

    Post an image from the guider?
     
  8. Marshall Edgell

    Marshall Edgell Cyanogen Customer

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    Doug

    My guide stars are wonderful. They measure out almost the same as on axis stars. I think I was faked out by an old image in my memory of fat bloated stars.
    This probably came about because when MaximDL shows a regular image the stars are nice and tight. But when it shows a guide image it's at high magnification giving fat bloated stars.
     

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