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Help me find a focuser!

  1. Sep 29, 2015 #1
    Can someone help me? I'm building a newtonian telescope, 8-inch, f/6, secondary minor axis 1.5 inch. According to the instructions I'm following, I need a 1.25" focuser with minimum fully racked in height of 1 3/4 inches. Problem is, I just can't seem to find a focuser with those specs. Are they that unusual? Could someone send me a link if you're able to find one? Thanks.
  2. jcsd
  3. Sep 29, 2015 #2


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    Staff: Mentor

    Welcome to PF!

    That's the racked-out length? That doesn't seem very long, but if you can't find one long enough you can always make them longer with extensions and diagonals. Also, if you want to do photography, you might prefer the heavier-duty 2". Have a look at this:
    http://www.telescope.com/Orion-2-Crayford-Style-Telescope-Focuser/p/13039.uts?keyword=crayford focuser
  4. Sep 29, 2015 #3


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    Staff Emeritus
    Science Advisor

    A minimum racked in height? That sounds like the racked in height an be larger than 1 3/4 inches, of which there are plenty of focusers.
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