focus problem with FW8G-STXL

Discussion in 'General' started by James Pothier, Apr 10, 2017.

  1. James Pothier

    James Pothier Cyanogen Customer

    Joined:
    Nov 15, 2015
    Messages:
    5
    Location:
    Sudbury MA
    I have the following setup that I am putting together:
    CDK17, STXL-11002, FW8G-STXL, AOX and I found that when I focus the main imager the 11002 and then try and focus the guider in the FW8G-STXL it hits it's end limit just shy of reaching focus. And prior to trying to focus the guider I positioned it as close to the main imager as possible without shadowing it. I am rather surprised this could happen. Any thoughts as to what can be done ?
     
  2. Doug

    Doug Staff Member

    Joined:
    Sep 25, 2014
    Messages:
    3,344
    Are you hitting the limit of outward movement ("tightening" the adjustment screw) or inwards ("loosening" the adjustment screw)?
     
  3. James Pothier

    James Pothier Cyanogen Customer

    Joined:
    Nov 15, 2015
    Messages:
    5
    Location:
    Sudbury MA
    I need to look at it again. Despite my best effort in taping off the pickoff mirror adjustment knob, I actually taped off the focus so I think I swapped them around. Sorry to jump to conclusions.
    Jim
     
  4. James Pothier

    James Pothier Cyanogen Customer

    Joined:
    Nov 15, 2015
    Messages:
    5
    Location:
    Sudbury MA
    The weather finally cooperated and I was able to determine that I did swap around the adjustment knobs in my mind and was trying to adjust the focus with the positioner. Strangely enough the positioner did change the focus more than I would have thought. But I am still having problems with getting the guider to image link in SkyX. I did succeed once or twice but most of the time it fails. And I am trying to use that information to precisely position the guider location on my FOV indicator relative to the main imager.
     
  5. Doug

    Doug Staff Member

    Joined:
    Sep 25, 2014
    Messages:
    3,344
    Yes the mirror position does affect the focus. If you think about the geometry a bit you'll see why - when you move it inwards, it is farther away from the guide sensor.
     

Share This Page