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people use one encoder to measure the hour angle at which a telescope
is pointed;  with the drive motor on,  this encoder reads a changing
value as the scope moves. Other people, though, will use one encoder
to measure the RA at which the telescope is pointed.  In such a case,
the drive motor doesn't force the encoder to move.

   Unfortunately,  Guide has no way to determine which system you're
using. So when you add the first alignment star,  it will ask you for
this information.

   Click on the "Scope Pad" option,  and you'll get a small dialog box
with assorted scope control commands.

   The next step is to add at least two alignment stars.  To add an
alignment star,  you first find it in Guide (by panning,  or using "Go
To..." commands, or whatever you wish) and clicking on it with the right
mouse button.  When you get the short dialog box describing the star,
click OK.

   Next,  point the telescope at this alignment star.  Once you have it
centered,  click "Add Alignment Star" in the scope pad.  Guide will add
that point in the sky to its alignment database.

   After you have added at least two alignment stars,  you can actually
get some pointing feedback from the telescope.  Click on "Slew Telescope".
Guide will read the encoders at one-second intervals,  putting a red circle
on the screen to indicate where the scope is pointed.  If the scope is
pointed off-screen,  Guide will force a redraw and then put the red circle
on the screen.  This is useful in aiming the telescope;  you set a wide
field of view,  click "Slew Telescope",  and push the telescope until
the indicator circles the target.

   Once you're done with this,  clicking on "Slew Telescope" again will
shut off the red-circle updates.

   Alternatively,  clicking on "Slew Guide" will cause it to read the
encoders once,  resulting in the chart being redrawn at the current
telescope position.

   Adding still more alignment stars can improve pointing accuracy
considerably.  If you find that the accuracy is poor in a given part of
the sky,  it's advisable to find a nearby bright star and to add it as
another alignment star.  This gives Guide an idea as to the amount of
error in that part of the sky;  it can then compensate accordingly.

   At present,  there is no command to delete the alignment data;  and
this is something you'll want to do if you move the scope or shut down
the encoders.  To clear alignment data,  delete the file ALIGN.DAT in the
Guide directory.

12:  PRINTER SETUP AND PRINTING     


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