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Re: Geometry of SNO-T

From: Herbert Prinz (no email)
Date: Thu Oct 14 2004 - 13:25:11 EDT

  • Next message: Alexandre Eremenko: "Re: Geometry of SNO-T"

    Alexandre Eremenko wrote:

    > On Thu, 14 Oct 2004, Herbert Prinz wrote:
    >
    > > But let's assume for the sake of argument
    > > that you have a perpendicularity error
    > > of 5' that you cannot get rid of.
    >
    > How can this be that you cannot get rid of it?
    > You mean if the adjusting skrew is damaged?

    This was in the context of a potential impact of non centred mirror
    surface on sextant performance. I was addressing the hypothetical case
    where you can't determine perpendicularity error any better on account
    of the protruding front silvered mirrors. Seas of 4' to 6' will be
    enough to make the use of cylinders impossible. Then you are limited to
    the rough method of looking at the arc. The 5' are just a wild guess on
    the high side. I have never noticed a problem with my Astra.

    How do your visors work? Can you clamp them on?

    Herbert Prinz


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