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    Re: a question of time or times
    From: Gary LaPook
    Date: 2011 May 30, 01:52 -0700
    That is one of the disadvantages to using zone time, always have to figure an adjustment for your actual longitude difference from the standard meridian. On a slow moving sailboat keeping "ship's time" by ringing eight bells at the time of the noon sight, "make it noon and turn the glass and pipe the crew to supper" as Captain Aubry would say, the advantage is that morning twilight, sunrise, sunset and evening twilight will happen at just about the same time on the ship's clock every day so you can leave the alarm on your alarm clock set as long as you adjust your alarm clock to ship's time and not miss the morning stars.
    gl

    --- On Sun, 5/29/11, Greg Rudzinski <gregrudzinski@yahoo.com> wrote:

    From: Greg Rudzinski <gregrudzinski@yahoo.com>
    Subject: [NavList] Re: a question of time or times
    To: NavList@fer3.com
    Date: Sunday, May 29, 2011, 4:07 PM

    Alan,

    At sea it is standard practice to stay on the zone time that is within 7* 30' longitude or less of the nearest zone meridian. This makes figuring sunrise, sunset, civil twilight, and LAN within 30 minutes of the NA listed time. Figuring the actual time for NA time listings requires an arc to time correction from the DR longitude to the zone meridian. Also be aware that most tide tables use standard time so an hour has to be added to get to daylight time.

    Greg Rudzinski
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