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    Re: Lunar photo
    From: Don Seltzer
    Date: 2014 Jul 22, 07:59 -0400

    Norm, your reasoning is fine.  When I first posted this photo, I had
    made a similar estimate of about 2 or 3 miles based upon the beam of
    the ship and the size of the moon.
    But a contradicting inconsistency is the apparent relative heights of
    the fore and main masts in the photo.  In a square-rigged ship, the
    main mast and its yards are always as least as tall as the foremast
    and its yards, and usually even loftier.  If this photo had been taken
    from miles away with a telephoto lens, these relative heights would
    have been preserved.  But instead, in the photo the foremast appears
    to be the taller, and if you pick out the individual yards, each of
    those on the foremast are higher than their counterparts on the main
    mast. This is due to perspective, with the camera located low down and
    at most a few hundred feet from the ship.
    Don Seltzer
    On Tue, Jul 22, 2014 at 12:16 AM, Norm Goldblatt
    > My reasoning was different. I assumed a mast height of about 110 ft. You
    > must be a distance of roughly 2.3 mi for the mast to subtend angle of 1/2
    > degree and hence look roughly the 'size' of the moon.
    > I could imagine photographer and helmsman being in communication to orient
    > both boats properly for a quick shot, no?
    > View and reply to this message

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