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correct.  Also, if you have the "show ground" or "horizon objects"
options set in the Background dialog, these may appear tilted.

   If you select "alt/az (zenith up)",  the chart will rotate to show
the zenith (point directly overhead) at the top of the chart. If you've
entered your latitude and longitude correctly, and if the clock is set
to the right time and time zone,  the chart will now appear "right side
up",  and will match what you see in the sky.  If you have the horizon
turned on, and it happens to be in the field of view,  it will now be
drawn straight across the screen,  instead of at an angle. Since Guide
is still centered on the same point in the sky, the effect will be to
take the chart and rotate it, possibly until it is upside down.

   Having the zenith at the top of the chart is particularly useful if
you have an "altitude/azimuth" type of telescope mounting,  such as a
Dobsonian.  It is also useful for making charts showing a large part of
the sky (i.e.,  low level numbers) for naked eye observing.

   The last two radio buttons,  "Ecliptic north up" and "Galactic north
up",  are not nearly as useful.  But sometimes,  people do want charts
aligned with these systems.

9:  OVERLAYS MENU        

   The Overlay menu lets you create and edit your own overlays, showing
lines,  circles,  and text,  on top of the charts. It also provides a
few example overlays,  showing constellation borders,  names,  and
outlines,  plus the pages in the AAVSO atlas and the plates in the
Palomar Sky Survey.

   For example,  you can use your own overlays to show areas you want to
view in an observing session,  or to label some objects or points of
interest,  or to add comparison magnitudes to a chart,  or for any other
use.  When you enter the Overlay menu,  it will look like this:

Edit Overlay
Toggle overlay on/off
User Object Menu
                                                           
   When you select "Toggle overlay on/off",  Guide will list the
existing overlays.  You can select one,  and Guide will provide a small
dialog box offering controls turning that overlay on or off,  setting
its color, and specifying the fields of view at which that overlay is
shown.  For example,  constellation lines are (by default) shown in
green,  and at fields from 9 to 91 degrees across. (When you're looking
at a larger field,  such as a full hemisphere, the constellation lines
get crowded and in the way.  Below 9 degrees, they cease to tell you
much of anything.)

   If the overlay in question is already appearing on-screen,  then it
is usually easier just to right-click on it,  then click "Display".

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