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    Extreme Nearsightedness--Focusing at infinity without eyeglasses

    Yes indeed. I think this is one assembly aspect that probably receives less attention than the synchronicity of focussing lenses at zero dioptre setting. Either excess overtravel at the expense of close focus or vice versa. John
  2. T

    Extreme Nearsightedness--Focusing at infinity without eyeglasses

    Lee, Rays reaching the pupil of the naked eye from a distant object would be parallel and binocular or telescope users with normal vision would adjust the focusser so that the rays from the viewed point source emerging from the eyepiece would also be nearly parallel for a relaxed view. The...
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    Extreme Nearsightedness--Focusing at infinity without eyeglasses

    Hi, First of all, I don't think your ability to discern fine detail at close range has anything to do with your assessment of a binocular's optical deficiencies. Perhaps you have an above average visus. A binocular is an afocal device and a user with normal vision would adjust the focusser so...
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