AO-x + FW5 + STX16803

Discussion in 'Guiding and Adaptive Optics - StarChaser and AO' started by Derek Kuhl, Aug 9, 2015.

  1. Derek Kuhl

    Derek Kuhl Standard User

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    I am trying to build this imaging train. I have an STX16803 (old style RGH connector) and a FW5 with 65mm filters. I would like to add the AO-X. How do I use the guider in this setup? Do I need to add another off axis guider to the train like a MegaMOAG + the RGH?
     
  2. Doug

    Doug Staff Member

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    Yes the Monster MOAG will work with a remote guide head and AO-X, although you may need a custom adapter to connect them. Unfortunately we don't have any of the old-style remote guide heads. There were only a couple left when we took over last year, and they've both since sold.

    You can however use the STX's built-in guide sensor with the AO-X.
     
  3. Derek Kuhl

    Derek Kuhl Standard User

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    Thanks fro the reply Doug. I think I have gotten a line on a compatible remote guide head. We will see how it works when it shows up.

    Yes there is the built in guide sensor. I was of the assumption that it would work poorly guiding through the filters especially Ha. Am I wrong in that assumption? I would love not to add additional complexity to the imaging train.
     
  4. Doug

    Doug Staff Member

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    Yes finding bright enough guide stars can be a problem with narrowband filters.
     
  5. Derek Kuhl

    Derek Kuhl Standard User

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    I have a followup question. I have read some of Alan Holmes posts and they imply that I could get data guiding images for the AO-X from an external guide scope rather that an off axis guider. I have always assumed that an off axis guider would be required. Is an off axis guider truly required or is there precedent for using an external guider scope with adaptive optics.

    The main reason I am asking is that I am running out of backfocus. The STX+FW5+AO-X+MMOAG+rotator take up more than the 193 mm of backfocus that I have.
     
  6. Doug

    Doug Staff Member

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    Yeah I know Alan has said that, but AO guiding really wants to be closed loop. Using an external guide scope would be open loop, so it would have to be extremely well calibrated to work, and I'm sure it would still drift off over time.

    We are working on a solution for the backfocus problem, though I don't think it will launch this year.
     
  7. Derek Kuhl

    Derek Kuhl Standard User

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    Thank you very much Doug. That is what I suspected. Now I am going to have to beg Ashley Stevens at Precise Parts to do what can't be done.
     
  8. Derek Kuhl

    Derek Kuhl Standard User

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    Does the off axis guider have to be looking through the AO-X? In other words, does the order need to be camera + filter wheel + MOAG + AO-X or can the order be camera + filter wheel + AO-X + MOAG.
     
  9. Doug

    Doug Staff Member

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    The off-axis guider needs to look through the AO-X.
     
  10. Derek Kuhl

    Derek Kuhl Standard User

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    Thank you Doug! You just saved some tears.

    Derek
     

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