Next message: Alexandre E Eremenko: "Re: Buying a sextant- a cautionary tale."
Alex wrote
> I use two pairs, one is Castor-Pollux, 4d30'.3 apart, another
> delta-zeta Orion, 2d44'.2 apart. I use essentially the same method as
> with the Sun: bring the pair together once on the arc, another time
> off the arc. The average gives me (the negative of) IC,
> and the difference twice the distance for control. My sextant permits
> to measure up to -5d (off the arc).
I am not clear about your method. Are you superimposing the point sources
in a clockwise and anti-clockwise direction, or trying to achieve tangency
(either in one direction or two directions of drum turns)? Either way,
unless your IE is way of, I don't see how you can wind up off the arc with
star-to-star angular differences in the 3d to 4d range.
Bill
