*Log In*
To Log In to a CLEA Exercise:

    1)  Select "File"->"Log In..." from the main menu.  The login dialog
    will appear.

    2)  Enter the appropriate name(s) in the fields provided.

    3)  The laboratory table number may already be set.  If it is not,
    or is incorrect, enter the correct table number.

    4)  Select "OK".  The selections on the "File" menu that control the
    exercise will be activated, while the "Log In..." selection will be
    deactivated.  (You cannot return to the login dialog after you have
    completed it.)

The information entered on the login dialog is used to generate names
for data files, and will appear on data and printouts that are produced
by the exercise. If you have entered no information, a box will warn you
of this when you press "OK".  If you select "Cancel" on the warning box
you will return to the login dialog.  If you select "OK" on the warning
box, the program will continue.  In this case, generated data and files
will be identified as "NoLog".

*Access Telescope Window*
In order to take spectra, you must access the telescope window.  Select
"File"->"Run"->"Take Spectra" from the main menu and the telescope
window will appear, showing the telescope control panel.

It is not necessary to access the telescope window in order to classify
spectra you have previously taken and saved, or spectra on the Program
List.

See Also:
    "Access Classification Window"
    "Load Spectrum and Standards"

*Telescope Controls*
The following buttons are used to operate the telescope.  They are
located on the right-hand side of the telescope control panel.

    Dome: Press this button to open and close the dome.  This is the
    only button that is enabled when the dome is closed.  The dome is
    closed when a telescope is first accessed, and closes automatically
    when the user elects to change telescopes. (See "Change Telescope")

    Tracking: This button turns on the sidereal tracking that enables
    the telescope to remain pointed at a particular spot on the sky as
    the earth turns.  When tracking is off, the stars will drift through
    the telescope field.  Tracking is off when a telescope is first
    accessed.  The other telescope controls are enabled only when
    tracking is on.

    Slew Rate: This button sets the rate at which the telescope moves
    when a slew button (N,S,E,W) is pressed.  The rate doubles each time
    the slew rate button is pressed, up to a maximum rate of 16.  The
    rate resets to 1 if the slew rate button is pressed when the rate is
    16.

    Slew Buttons (N,S,E,W): The slew buttons are used to move the
    telescope to point to a particular spot (direction) in the sky.  To
    move the telescope, press and hold the appropriate button.  The
    telescope will slew at a speed determined by the slew rate setting.
    Release the button to stop the slew.  For long slews, the button
    will stay down if you slide the cursor off of it before releasing
    the mouse button.  In this case, stop the slew by pressing and
    releasing the mouse button with the cursor over any slew button.

    Monitor: The telescope has two magnifications (or field sizes)
    available.  The "Finder" field is 2 1/2 degrees on a side, and is
    used for locating particular stars and other objects.  The
    "Spectrometer" field is 15 arc minutes on a side, and is used to
    center the object on the spectrometer slit, which appears in the
    center of the spectrometer field.  (The small square in the center
    of the finder field shows the relative size and location of the
    spectrometer field.)  The spectrometer is enabled for use only when
    the spectrometer field is displayed.  The "On" indicator light
    located next to the Monitor button shows that the monitor screen is
    displaying the view through the telescope.

    Set Coordinates: Pressing this button activates a dialog which
    allows the pointing coordinates for the telescope to be entered
    directly.  This is generally faster than using the slew buttons to
    move the telescope from object to object, unless the objects are
    very near each other in the sky.  Some "fine tuning" with the slew
    buttons may be necessary to center the object in the spectrometer
    slit after setting the coordinates.

*Request Telescope Time*
Access to the larger telescopes may be restricted.  You may request time
on telescopes that are not currently available to you (the selections
are grayed).  To request time, select "Telescope"->"RequestTime"->
(telescope selection) from the Main Menu.

If your request is granted:
    You will be informed of the number of uses you have been given (the
    number of spectra you can take with the restricted telescope).  You
    may then access the telescope in the normal manner (see Help topic
    "Access Telescopes"), but a tally will be kept of your uses, and you
    will be informed when you have "used up" your allotment.  You may
    then request more time if you wish.

If your request is not granted:
    You will be informed that you may reapply after a certain number of
    minutes.  Until that time has passed you will not be able to request
    time on that particular telescope.  When the time has elapsed a
    message will appear informing you that you may reapply.  You may do
    anything else you wish, including requesting and/or using other
    telescopes, classifying stars, etc. while waiting to reapply.


*Access Telescopes*
To change telescopes, select "Telescope" from the main menu, and then
make your selection from the "Access" list that appears.  If a
particular selection is grayed, you must request and be awarded time on
that particular telescope - see Help topic "Request Telescope Time".

When you have selected a telescope to access, the dome on the current
telescope will close, and there will be a pause while the system
attempts to access the telescope you have selected.  If the selected
telescope is available, you will be given control.  Note that you must
again open the dome and turn on the tracking before you can proceed to
take spectra with the new telescope.  If the telescope you select is
restricted and you have been granted a limited number of uses, you will
be informed of your remaining uses before the telescope is accessed.

*Change Star Field*
The "Field..." selection on the main menu accesses a dialog from which
you can select other star fields, if your exercise involves multiple
fields.  Note that the field cannot be changed unless the dome is open
and the tracking drive is on.

*Access Spectrometer Window*
You can access the spectrometer window only when the spectrometer (15
arc minute) field appears on the monitor.  After you have carefully
centered the object in the spectrometer slit using the slew buttons,
press the "Take Reading" button and the spectrometer window will appear.
The spectrometer window has its own menu to control taking and saving a
spectrum of the object in the slit.  Note that some selections from the
main menu remain available when the spectrometer window is displayed.

*Start/Resume Count*
Select "Start/Resume Count" from the spectrometer menu to begin/continue
integrating the spectrum.  You will see the spectrum begin to take a
recognizable shape as the counts build up in each of the 500 channels of
the spectrometer.  (The display is always normalized to the highest
reading in any channel, so that as time passes you see the noise
decreasing rather than the counts moving upward.)  Note that the object
name, apparent magnitude, current photon counts, integration time, and
signal-to-noise ratio are displayed below the graph.

*Stop Count*
Selecting "Stop Count" causes the integration to pause.  The display is
redrawn with lines connecting the adjacent channel readings for clarity.
You may stop and resume as many times as you like, the integration
always continues from where it left off.  (You cannot "lose" a spectrum
unless you return from the spectrometer window without saving it.)

*Measuring Spectral Features*
You can measure the position and relative intensity of spectral features
when the count is stopped.  Press and hold the left mouse button as you
position the cross-hair cursor on the feature you wish to measure.  The
position of the cursor appears on the screen in X,Y coordinates
(pixels), and in converted form as wavelength and relative intensity.
When you release the left mouse button the cursor returns to an arrow
and the last reading remains on the screen.

*Print Spectrum*
To print the current spectrum, select "Print" from the spectrometer
menu.  The spectrum is printed as it apppears on the screen, along with
identifying header information.  Printing is accomplished via Windows,
employing the Windows Print Manager if so specififed in the Windows
setup.  Output is directed to the default printer, also specified in the
Windows setup.

*Save Spectrum for Classification*
You cannot classify a spectrum you have taken unless you save it.  When
you feel the signal-to-noise ratio is sufficiently high for accurate
classificaion (around 100, but lower values may suffice for some
spectral types), stop the count and select "Save" from the spectrometer
menu.  You will be asked to provide a 3-digit ID number for the
spectrum.  This number is combined with five letters from the first name
on the login record to create a file name (qualifier .CSP).  You will be
asked to verify the file name.  If a file of that name already exists,
you will be warned before the existing file is overwritten.

If you are not sure that the spectrum you are taking is sufficient for
classification, and you may want to return to the spectrometer window
and continue integrating it, use the following technique:

    1)  Save the spectrum.

    2)  Do NOT select "Return" on the spectrometer window.  If you wish,
    you can minimize the spectrometer window via the box in the upper
    right corner, but this is not necessary.

    3)  Select "File"->"Run"->"Classify Spectra" from the MAIN menu.
    Load the file you just saved and attempt to classify it.

    4)  If the spectrum is too noisy for accurate classification, you
    can continue to integrate it.  Return to the spectrometer window and
    select "Start/Resume Count".  When you are finished you will have to
    save it again (you can overwrite the old version), and reload it
    into the classification window.

*Return to Telescope Window*
Select "Return" from the spectrometer menu to close the window and
return to the telescope control window.  If you do this, you cannot come
back to the spectrometer and continue integrating a spectrum from where
you left off, although you can start over again with the same star.  If
you have not saved your current spectrum you will be warned and given a
chance to do so before the spectrometer window is closed.

See Also:
    "Save Spectrum for Classification"

*End Exercise*
Select "File"->"Exit" from the main menu to end the exercise.  If you
have taken and saved any spectra they will remain in the machine.  You
can restart the program and access them for classification at a later
date.

Warning: Be sure all your classification data has been saved and printed
(if desired) before ending the exercise.  You must perform these
actvities from the Classification Window.

*Access Classification Window*
In order to classify spectra, you must access the classification window.
Select "File"->"Run"->"Classify Spectra" from the main menu and the
classification window will appear.  It is not necessary to access the
telescope window before accessing the classification window.


See Also:
    "Access Telescope Window"
    "Save Spectrum for Classification"
    Topics under "Help" on the classification menu
