Hi folks,

Thanks to all for the comments on getting scopes to track moving
targets. Celestron has added a "move at speed A on this axis and
speed B on that axis" to its latest command set, and given their
rivalry, Meade will doubtless do likewise. I only wish they'd
done it a long time ago.

Most of the replies I got, both on and off-list, mentioned
www.heavenscape.com . After I get the basics of scope control
wrestled into coherent shape, I may be checking there to get
some ideas as to how to implement this sort of thing.

Robert Burns asked about adding one's own FITS images to
Guide. This is not exactly _easy_ to do. You have to run the
image through Charon:

http://www.projectpluto.com/charon.htm

a program originally written for people doing asteroid astrometry.
It was only much later that it occurred to me that, once an image
is registered to a star catalog and you know where its corners are,
it could be shown in Guide, properly aligned with everything else.

I may add in an alternative "pretty picture" scheme, in which
one could take an image (including color ones) and rotate/scale/move
them by hand until they line up properly:

http://www.projectpluto.com/future.htm#pretty_pictures

The next update I post will give, in 'more info' for asteroids
and comets, rates of motion on each axis. (A speed and position
angle are currently given.) Thus, you get comments such as

Speed of apparent motion: 2.999'/hour at position angle 135.8
Motion is -36.15 RA minutes/day in RA, -51.85 arcminutes/day in dec

Units for the latter are almost infinitely adjustable, including
exotic and useless possibilities such as radians/fortnight or French
Republican degrees per hour. (360 "normal" degrees = 400 FR degrees.)

-- Bill