ZC-Tycho2/"second time"/etc.

Bill J Gray Jun 13, 2003

Hi Oliver,

I really should have simply posted the ZC-Tycho2 right away,
since I can fix the alignment problem later. But it is now posted:

http://www.projectpluto.com/extras.htm#zc_tycho2

Thanks for the comment on the origin of "second time". Now
I know whom to credit when I write up the description of the
function for the update page.

I did notice the problem with the CCD frame, and have corrected
it. I had been working on a function to let Guide show an image
stretched over the frame; a user could say, "Here is a JPEG or
GIF I created, or downloaded from the Internet... stretch it over
the CCD frame, and I'll rotate it and shift it into its proper alignment
with the stars." Thus, one could add color images to Guide, and
there are plenty of nice Hubble images that could be added.

This seemed like a good idea, but when I tried it, I found that
it's miserably difficult to do the alignment, so I've dropped the idea.
But when I was working on it, I had to put the CCD frame into
the background, so that stars, etc. would plot on top of the image.
When I scrapped the idea, I failed to put the CCD frame back
where it was... but I've fixed it.

I was very interested in this comment:

"... At my experience it is better for the LX200 pointing accuracy to
update both times at the LX200: Local time and Local siderial. Both
times should be set by GUIDE. Is it possible to add two buttons for
time update at the telescope control?"

I must admit that I am a little confused at this. The LX200 knows
your longitude; given this and the local time, it should be able to
compute the local sidereal time without trouble. But I see that the
command set lets you "set local time", "set local sidereal time",
_and_ "set the longitude".

To me, it would make sense for Guide to be able to set the
telescope longitude and local time. I may try this, then check
to see if the LST is properly updated. If it is, it may be a better
solution. (I may also ask Meade why they provided a seemingly
unnecessary "set LST" function!)

-- Bill