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    Re: A guide to AH use
    From: Greg Rudzinski
    Date: 2014 May 17, 10:02 -0700

    Randy,

    Not sure what you mean by progressive focus. If you are using prescription glasses while making sextant observations then I suggest removing them. The scope focus already corrects for focal length issues so all you are doing is reducing your field of view by wearing spectacles. Navlist optometrists correct me if I'm wrong.

    Re: A guide to AH use
    From: Randall Morrow
    Date: 2014 May 16, 21:53 -0700
    Greg, thank you for your observation. In principle I agree. The focus should be at infinity because it is the objects reflection I focus on. But with the scope taken off, I looked at low objects standing way back, and I had to adjust my focus for a higher object that I stand closer to get. Shouldn't I be able to leave focus alone if all are at infinity? It may turn out to be the tilt of my head changing the progressive glasses focus. What do you think?
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