Thread: eye peace
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Old 13-08-2007, 09:33 AM
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Omaroo (Chris Malikoff)
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Omaroo is offline
 
Join Date: Aug 2006
Location: Hobart, TAS
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Starlight - is this so that you can estimate its position in the field of view before you swap for the camera? The DSI, I believe, has a focal length equivalent to about a 6mm eyepiece, so you'll need one of those to do what I think you want to do.

You'll also need to get a parfocal ring (a small ring that clamps around the eyepiece or DSI and "sets" it at a known bottom position when slid into the focuser. Use the parfocal ring to set the position of either the DSI or eyepice up or down so that both the camera and eyepiece are focused at the same point of focuser travel when sitting in that focuser. To do this, focus your scope with the 6mm eyepiece sitting in its natural bottomed position. Then, without changing the focusers position slip in the DSI fitted with a loosened parfocal ring. Slide it up and down in the focuser until you get the best fucus you can on-screen and then lock the parfocal ring at that point.

Then all you need to do is view through the eyepiece to focus, and when you're ready, swap immediately to the camera and it should already be in focus.

Cheers
Chris

Last edited by Omaroo; 13-08-2007 at 10:07 AM.
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