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    Re: Freiberger sextant
    From: Alexandre Eremenko
    Date: 2012 Aug 13, 17:52 -0400

    I 100% agree with your opinion.
    Some sextants have a vernier (on the 1' drum) reading to 0'2.
    Astra, if I remember correctly, and many British sextants.
    I think 1' drum with no vernier is sufficient for all purposes
    a sextant is used in XX century:-)
    BTW, speed and certainty of reading is also very important.
    And on my opinion, vernier/drum combination INCREASES the
    chance of blunders. (From my experience with Bill B. Astra).
    But a magnifier is great for twilight and for the Lunars:-)
    > Given the likelihood that no sextant can repeat a reading down to one
    > tenth
    > of a minute because of tiny amounts of "slop" between the tangent screw
    > and
    > the limb, vernier scales strike us as maybe desirable - but by no means
    > necessary - for accuracy.
    > Just one man's opinion. Anyone else have thoughts on this?
    > Ridge White
    > Robert E. White Instruments
    > PO Box 775
    > Medfield, MA 02052
    > Tel: 617-482-8460
    > Fax: 617-482-8304
    > On Mon, Aug 13, 2012 at 11:33 AM, Jeremy C  wrote:
    >> Hi All,
    >> I just took a ship from Anchorage Alaska to Singapore. She had onboard a
    >> Freiberger sextant, the first I had seen or used.
    >> Here's a photo: http://www.flickr.com/photos/37977699@N00/7774059416/
    >> I can't say that I was too impressed to be honest. It was fairly light,
    >> being all Aluminum, and the shades were nice. The unit was also well
    >> constructed and the movement of the arm and micrometer drum were silky
    >> smooth. Still the non-standard fork precluded the use of my 7x35 scope
    >> which was unfortunate.
    >> The biggest thing that bothered me was that the micrometer drum had me
    >> interpolate within 1' incriments. For a Lunarian, this is quite
    >> unacceptable. I want to interpolate at 0.1' or 0.2'.
    >> The weather on the 21 day trip was terrible for stars and shooting in
    >> general for my whole trip. I did manage a few sun lines which worked out
    >> well, but no stars. I will say that shooting at 60 deg N made this the
    >> closest to the pole I've ever shot. It's just too bad there was no
    >> chance
    >> to shoot a round of stars up there.
    >> Sadly the ship, MV VIRGINIAN, along with the sextant, will be on the
    >> beach
    >> being turned into razor blades in a few weeks, as the owners decided to
    >> sell it for scrap. So much for my second command. I guess that's the way
    >> of
    >> the shipping world.
    >> Jeremy
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    > View and reply to this message: http://fer3.com/arc/m2.aspx?i=120339

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