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    Re: Eyesight dangers using telescopes
    From: Bill B
    Date: 2009 Jun 26, 06:58 -0400

    Engineer wrote:
    > Diplomacy on this site is not always in evidence (no, not you Frank). Douglas
    > I hope will continue to be a valued contributor. Can we perhaps all resolve to
    > use  phrases such as "Are you perhaps mistaken?" as substitutes for more
    > direct and acerbic versions.
    I personally prefer the phrase uttered by Dabney Coleman's character in the
    film, "9 to 5."  Something like, "I'll be damned if I'm going to let some
    snot-nosed punk let my cheese hang out to dry."  It is pithy without being
    degenerate ;-)
    To Doug
    Seriously, I was a list newbie once with no clue, now I am semi-established
    member with no clue.  When the veteran gurus tell you it is possible, "trust
    then verify."  A new set of eyes thinking outside the established box may
    have something to add.  A new member telling a lot of folks that can do
    star-to-star distances quite well that they cannot be done does not solicit
    a lot of sympathy for your inability.  It has been pointed out in many posts
    that it is not easy, it takes practice, and there are techniques and tricks.
    The bait is out there, members are willing to share (it is the 90-% of the
    group exists) take the bait.
    In my case, a member that resided in the same town taught me many techniques
    and tricks.  Sit, find something to steady body/elbow/arm etc.  I could not
    do it well--if at all--at first.  Baby steps.  Start with bodies that allow
    you to hold the sextant in the  vertical position.  For more difficult
    observations take the scope off and eyeball one star then find the other
    star in the index mirror and get them close if not presetting based on
    calculations. Do that even with presets for awkward positions. That exercise
    also helps in developing a kinetic sense/memory of what
    contortions/circus-people positions you need to assume to make the
    observation.  If preset find a dim object star in the horizon mirror with
    scope and the presumed other bright object star in the index mirror, then
    switch the stars/mirrors and see if they still align.
    Try Frank's tip for lunars.  Get them close, relax and take a quick break.
    Get them closer and relax, then move in for the money shot.  In star-to-star
    distances there is no rush or pressure as they are not changing angular
    distances in a hurry.  Make several observations and average to reduce
    random error.
    It is very frustrating at first.  Even with practice, the process can throw
    you a few curves. I watched a veteran upset because his sextant was minutes
    off before realizing he was viewing a wrong star for the designated pair in
    the winter hexagon.  I have witnessed two observers with advanced degrees
    who should have known better sitting on the same side of a picnic table,
    leaning backwards to get the angle--which caused the center of gravity to
    shift so the table rolled over on them as they fell backwards.
    It was interesting that despite the fact both were falling on their backs
    and heads with a table on top of them they both came to rest in the same
    position--pinned under the table with the arm holding the sextant
    outstretched and vertical. No harm was done to the sextants.
    I would normally have found this humorous, but it took two trips through the
    washing machine to get the grass stains out of my jacket.
    Bill B.
    Navigation List archive: www.fer3.com/arc
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