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Re: Drum Sextants VERNIER READINGS

From: Yourname Here (no email)
Date: Thu Jun 16 2005 - 08:09:26 EDT

  • Next message: Ken Muldrew: "Re: Drum Sextants"

    Frank,

    Thank you for saying that.

    Some people think they are getting short changed when there is only the index and no hash marks. It should make no difference since you can visually estimate with great accuracy the intermediate reading. Power Squadron members sometimes confuse the USPS degree of sight reduction accuracy required with Ho.

    Where there are intermediate marks on a sextant's vernier they usually are:

    5 = 12 seconds arc
    6 = 10 seconds arc
    10= 6 seconds arc ( Navy MK III)

    Joel Jacobs

    --
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    http://www.landandseacollection.com
    -------------- Original message from Frank Reed <>: --------------
    > I've also noticed that some Plath sextants don't include a little vernier
    > scale for reading off tenths of minutes. But in practice, I find that this
    > matters relatively little. I can read to 0.2 minutes (which is as good as it
    > gets, in my practical experience) with or without the vernier scale.
    >
    > -FER
    > 42.0N 87.7W, or 41.4N 72.1W.
    > www.HistoricalAtlas.com/lunars
    

  • Next message: Ken Muldrew: "Re: Drum Sextants"



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