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    Best ages for taking Moon-Sun lunars
    From: Ed Popko
    Date: 2016 Sep 11, 13:58 -0700

    With moderating temperatures and clearing skys, I have taken to practicing lunars again. In so doing, I'm probably redescovering what everyone else already knows. But just in case ...  

    My goal is to have a good idea what days are best for shooting and what the approximate near-limb moon-sun angle will be to preset my sextant if I know the approximate GMT of when I'll be out shooting.

    September 2016 moons offered a new moon phase on the 1st (near so) and returned to new moon at the end of the month.  So I computed the geocentric sun-moon LD distances for each day at 12:00 GMT to see which moon ages are opportunities.

    From my limited experience shooting lunars, I know that about 90 degrees sextant arc is nearing my maximum angle for consistent results (getting under 45 seconds of GMT)  Shots beyond 90 degrees, say 110 degrees (moon ages 10 or 20) are very difficult for me.  I struggle to get times within a minute or minute and a half. My C+P sextant weighs about 6 pounds and its hard for me to hold it steady when the angle is more than 90 degrees. I usually have to lean on something (dock piling, car roof, edge of tree etc.) to be steady enough.

    I don't have enough experience with short angle sights like 30 to 60 degree to comment one way or the other.

    My best results are with waxing moon ages 3-10 or waning 20-26  (given the other current thread on "Lunar Contrast", if you are using polarizing filters, then waxing ages 7-9 and waning ages 21-23 seem best.)

    In our area, clouds and haze build in the afternoon which hinder waxing moons.  For myself, early or mid-morning waning shots, have always produced best results (within 15-20 seconds of GMT).

    I'm interested in any rules of thumb other NavList lunarians about the best ages of sun-moon lunars to shoot and preset advice (other than computing the geocentrics for the approximate shooting time).

    Ed Popko

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