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~dalign 32       # The text labels are aligned at the bottom left

   The first line tells Guide that magnitudes are stored in columns
40-44 of each record.  This will be used in,  for example,  determining
the size at which stars are drawn.

   Along with the "sizs" (size in decimal seconds),  one can use a
"sizm" (size in minutes) or "sizd" (size in degrees). "resize" is
useful for converting a diameter to a radius (as shown above),  or
for converting from arbitrary size units.

   The "text" line tells Guide what data to use in labelling objects (if
any; some datasets don't have any designation to add to the object.)

   If the dataset doesn't start right at the beginning of the file, you
will have to add the "offset" keyword to tell Guide how many bytes to
skip.  This will always be needed with FITS files.

   In general,  if you are dealing with simple text files, you can
ignore the "line size",  "nlines",  and "sort" keywords.  But if every
record is exactly the same length (as happens in many text files and in
all FITS files),  it can improve speed if you provide these fields.  If
the dataset has no carriage return or line feed at the end of each
line,  they are absolutely essential.

   If you've provided "line size" and "nlines",  _and_ the data is
sorted in order of increasing RA,  then it's a good idea to add the
"sort 1" keyword. If Guide knows the dataset is already sorted,  it
can skip over large amounts of data and draw your dataset _much_
faster! Fortunately, many datasets are provided in this order,
and/or are small enough to make this improvement less important.

   Also,  you'll need to provide a "type" keyword,  to tell Guide how
to display the object.  The pre-defined values for "type" are...

~d0 = open clus
~d1 = globular
~d2 = diffuse neb
~d3 = planetary nebula
~d4 = galaxy
~d5 = OC & neb
~d6 = star
~d7 = circle/ellipse
~d8 = radiation symbol (for X-ray or gamma-ray sources)
~d9 = radio dish (already used for all catalogs in RADIO.TDF)

   For all types except 6 (star),  the symbol size will be scaled by the
"sizs" (or "sizm" or "sizd") data.  Stars are sized by the "mag" data.
For type 7,  if a "siz2" field is supplied,  it specifies one (usually
minor) axis of an ellipse,  with the "size" field supplying the other
(usually major) axis.  If no "siz2" is supplied,  you just get a circle

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