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    Dioptric correction
    From: Norm Goldblatt
    Date: 2013 Jan 21, 12:15 -0800

    After 60 years of using my right eye for telescope viewing, I realized that my left eye is MUCH better. I've been training myself to use it and interestingly, it's difficult. What hope does an unfortunate celestial navigator have?

    On the same issue, I'm looking at my lovely Troughton and Simms optics and I realize there is no adjustment to accomodate dioptric correction. Is this common in the old instruments? Is the depth of field sufficient to make adjustment un-necessary? My collection of telescope tubes, lenses, etc. is in quite a state of disarray to the extent that I really can't seem to bring any combination into focus without extending eyepiece or objective beyond it's threads. I did notice that I have one tube that seems to telescope into the other tubes, but can't get the right combo, as two of the tubes have reticles in them.

    Suggestions welcome
    Mountain View, Ca.
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