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Get UCAC-3 from Internet
Get CMC-14 from Internet

   The A2.0 catalog was originally distributed on a set of eleven CDs,
consuming a total of 6.3 GBytes.  This is not much on a modern
hard drive.  If you have copied part or all of A2.0 to your hard drive,
then Guide can just display it on the charts in the same manner as stars
from any other catalog.  To do this, you need to edit the file GUIDE.DAT
with a text editor (such as Notepad) and add a line such as this:

A2_PATH=14.3;c:\a2

   The above line would tell Guide that if it's showing stars fainter
than magnitude 14.3,  it should show A2.0 stars.  (If the current
magnitude limit is brighter than this,  there is probably not much
point in showing the Ax.0 stars.)  It also tells Guide that the Ax.0
files can be found in the \a2 directory of the C: drive.

   Alternatively,  you can hit Alt-J and enter the A2_PATH line you want.

   As the catalogs became larger,  distribution on CD-ROM and DVD
ceased; the remaining catalogs are only available via Internet.  You
must first zoom in to the area for which you want data;  then click
on any of the "get (star catalog) from Internet" options,  and Guide
will make a request of the VIZIER astronomical data server at the
University of Strasbourg,  in France,  for data covering that area.
After a pause to download the data,  the screen will be redrawn with
the new star catalog data shown.

   As with most objects shown in Guide,  you can then right-click
on any of the downloaded objects to get information about it,  and
get "more info" or click on "display" to get control over how that
catalog is displayed:  the fields of view at which it is shown,
whether catalog IDs are shown as labels for each object,  the color
used,  and the limiting magnitude used.

   Downloads of each of these datasets accumulates.  If you want
to clear the data,  right-click on an object,  then on "More Info".
You'll see an option there to clear all the stars from that catalog.

   All of the Internet-downloaded catalogs are implemented as
user-added datasets.  You can go into Extras... User-Added Datasets,
click on (for example) "2MASS data (downloaded from VizieR)",  and
see the controls over that dataset.

   Of course,  you may well wonder what each of these catalogs are.
Each has strengths and weaknesses in terms of accuracy,  number of
stars contained,  and the sort of data given for each star.

   The USNO A1.0 and A2.0 catalogs are the eldest of this group,
dating back to 1997.  A2.0 is an update to A1.0,  with recalibrated
(improved) magnitudes and positions,  but they are frequently lumped

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