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Old 24-02-2013, 09:28 PM
dave brock's Avatar
dave brock
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Join Date: Dec 2011
Location: hamilton nz
Posts: 71
Quote:
Originally Posted by racecar View Post
It surprised me that I could focus on a near object holding the objective at arm's length. I could not get it to focus at infiinity, which was a relief, because I don't know how easily i could figure an F4 or F3.
That's a little worrying because as you focus on closer objects, the focal point moves away from the primary. That is, if the mirror is 36" focal length for infinity then the distance you need to hold the eyepice for a closer object will be, say, 37"-39" for example. Have you done a focal length test?

Dave
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