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    Re: Summer Solstice
    From: David Pike
    Date: 2016 Dec 23, 13:40 -0800

    Brad you wrote: To take the observation, we would place the AH mirror such that at the moment of observation, the in-plane tilt is known to 0.1' and the out of plane tilt is held to a minimum.  We will have arranged the tilt to be nearly all in plane, by planning for the azimuth of the intended observation.

    Yes, the sextant, the direction of the vertical plane of the mirror (possibly defined using pins in the base), and the Sun would all have to be in line.  You couldn’t just shuffle a bit to get the best view.  I’d missed that point.  You’d probably have to set the azimuth up first in advance; attempting to move the mirror in azimuth just before the shot would probably upset the rest of the settings.  You chaps work to an order of magnetude higher than me.  I've rarely worked to closer than a minute of arc.  DaveP

       
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