B1.0/assorted issues

Bill J Gray Dec 2, 2002

Hi folks,

Some comments on displaying a new (latest and greatest) star catalogue
in Guide and replies concerning time zone troubles, DSS display issues,
and trouble loading DOS Guide:

USNO B1.0 DISPLAY:

You can now display USNO B1.0 (successor catalogue to USNO A2.0)
in Guide:

http://www.projectpluto.com/extras.htm#b1

Be warned that this isn't easy to do yet. B1.0 is available through
exactly one source, a server at the Naval Observatory Flagstaff
(Arizona) Station, through a somewhat awkward interface. I have
hopes that eventually, you'll have the same sort of "zoom in on
an area and hit a button to get data" interface that is provided
for A2.0, GSC-2.2, and DSS images. But we aren't there yet.

I'd recommend A2.0 and/or GSC-2.2 for convenient access to star
data, and B1.0 for cases where you really want to get every possible
bit of information about a field. B1.0 includes magnitudes measured
from up to five plates. I suspect (but haven't confirmed yet) that
the photometry is more accurate than the previous sources.

TIME ZONE TROUBLES:

Makoto Yamasaki wrote:

"...When I try new test version of Guide8, it happens a problem in
time zone... My PC is set time zone to JST (+9 hour of GMT), Guide is
set time zone to JST, but Guide says it is PC's time- 9 hour. e.g. PC's
time=0:00:00, Guide's time=15:00:00 If I set Guide's time zone to GMT,
Guide's time=06:00:00."

I think I've found and fixed this problem. It was the result of an
"improvement" I had made to Guide's handling of time zone data from the
PC. It did fix some problems, but I made one small mistake that
(I think!) is causing trouble on your machine.

DSS DISPLAY ISSUES:

Dave wrote:

"...I have used software which will merge .fit images into
mosiacs, but these merged images do not display in Guide."

True; they probably lack the FITS header data that tells Guide
how to position the image in the sky. Best thing to do is to display,
not the merged images, but the "sub-images". Guide will mosaic them
on-screen.

"...Is there a way to open more than one image at once? If I have a
bunch of saved .fit files that I want to display, do I have to go
through each one individually?" Yes, you do.

"...Is there a way to clear a single .fit image, rather than having to
delete all of them?" Two ways: you can delete the .FIT file itself,
then edit the file 'realsky.dat' and look for the line describing that
.FIT file. (Each image gets one line in 'realsky.dat'.)

"...Is there a way to change the default contrast for .fit images?
I changed the environ.dat file, but new images continue to be loaded
at '1000,11000'." Um. At present, no (the field you found applies
to extracted RealSky images, not DSS ones.)

I still want to have contrast/brightness handled "sensibly" in Guide,
with the program actually examining pixel values to determine a reasonable
sort of default settings. In the meantime, I've added yet another
graceless hack. Add a line such as

DSS_CONTRAST=2000,12000

to 'guide.dat', and Guide will use this as the default setting for
downloaded DSS images.

"...(5) When DSS images are downloaded into Guide, are there extra files
stored in the Guide directory? I know about the 00xx.fit files, but
what are the x.B32 files?" The .B32 files contain numerically-integrated
ephemerides for outer planet satellites. Only thing you get with DSS
images are the image files themselves, plus lines added to 'realsky.dat'.

DOS GUIDE TROUBLES:

Bernard Heathcote wrote:

"...I'm running Guide8 under DOS, in conjunction with Bartels'
scope.exe and I've had no problems with this combination until I
installed DOS CDROM drivers. Now, when I try to load DosGuide, I get the
error message 'DOS/16M error [13] cannot allocate transfer buffer'."

No real idea on this one. Best I can suggest would be to check
out the available switches for the CD-ROM drivers. There are probably
some involving use of extended memory; these might, I suppose,
somehow conflict with the way the DOS extender used by 'dosguide.exe'
works. (I'm being vague here simply because I never had occasion
to find out the details of how DOS extenders work... just as well;
the knowledge would be somewhat obsolete now!)

-- Bill