Leisure Time LX20 - Manual (Page 17)

options, which are; ALTAZ, POLAR, and LAND.
Assuming that you have already entered correct local time,
latitude, and longitude (see QUICK START, page 9) you are
ready to choose a particular type of alignment, by pressing
the NEXT or PREV key to run the arrow beside the desired
option of ALTAZ, POLAR, or LAND, and then pressing the
ENTER key. The display will then give you specific
instructions from this point that will literally walk you through
the chosen alignment type.
a. ALTAZ: ALTAZ (Altazimuth) requires that you mount the
LX200 directly to the top of the field tripod (with the
power panel facing North), and adjust the leg extensions
of the tripod until the instrument is level. You are then
required to align on one or two of the bright stars in its
look up table of 33 alignment stars. This allows your
LX200 to track in altitude and azimuth simultaneously
for visual observations, or very brief (under five
minutes) exposure astrophotography or CCD imaging
(longer exposures will require the Field De-Rotator).
ALTAZ allows you to fully access the Object Library as
well as all other telescope functions. Complete
instructions for using ALTAZ are in the QUICK START
(page 9).
b. POLAR: POLAR allows you to use the 16" LX200
(mounted on a permanent pier set to your latitude) as
an equatorial telescope. With the LX200 powered up,
the POLAR file option selected, and the field tripod
leveled, the telescope should be adjusted so that the
Declination setting circle (3, Fig. 1) is set to 90 degrees
and the telescope is rotated to the 00 hour angle (HA)
position in Right Ascension. In this position, the
viewfinder (Fig. 1) is up-side down, and the R.A.
pointer (4, Fig. 5), the 00 line of the R.A. setting circle
(3, Fig. 5), and the HA pointer (5, Fig. 5) all line up. (If
you do not start at the 00 H.A. position, the telescope will
point to the ground instead of the sky, when the keypad
display chooses its second star.) Press the ENTER key
and the LX200 will determine and slew to the precise
off-set of the pole star in Declination and Right
Ascension.
At this point you need only aim the instrument at the pole
star (see APPENDIX C, page 31, if the pole star is not
visible) and center it in the eyepiece field using only the
altitude and azimuth adjustments on the pier. Once
done, you again press the ENTER key and the LX200
will choose and slew to a very bright star that is
overhead and can usually be seen in the field of view of
the viewfinder. At this point, center the bright star using
only the Right Ascension and Declination adjustments
of the telescope (either manually by loosening the locks
only or electrically), then press ENTER. You can now
access every every function of the LX200.
c. Refined Polar Alignment: Astrophotographers
routinely require polar alignments of the highest
accuracy for the finest guiding characteristics. Your
initial polar alignment can be refined by using the
LX200's electronics by using a slightly different method
in the POLAR menu option. The steps outlined below
should be performed in two or three 15 minute intervals.
At each interval the telescope will slew to the area
where the pole star should be centered in the optics.
You may find that the pole star is somewhat off-center in
the eyepiece showing the alignment error that may have
been made during your initial setup. Re-center the pole
star during each interval using the tripod adjustments
only (see APPENDIX B, page 29) in altitude and azimuth,
then follow the rest of the routine.
Return to the POLAR menu option in the
TELESCOPE mode and press the ENTER key.
Ignore the keypad display instructions to return the
telescope to 90 degrees in Declination and 00 HA.
Instead, press the GO TO key and the LX200 will slew
to the calculated position of where the pole star should
be.
Re-center the pole star in the field of view in the
eyepiece using only the adjustments on the pier in
altitude and azimuth.
Press the ENTER key, and the LX200 will once again
slew to a bright star overhead. Center this star using
the N, S, E, or W keys, then press ENTER.
NOTE: Pressing the MODE key at any point in the
alignment routine aborts the routine and exit to the top
menu.
After each 15 minute interval you will find that the pole
star becomes more accurately centered each time. You
can repeat the intervals as often as you like to obtain
the highest accuracy. An optional illuminated reticle
crosshair eyepiece makes the job of centering the star
easy.
There may be situations when it is impossible to see the
pole star due to something blocking your line of sight.
On such an occasion, just press the ENTER key for the
POLAR option so that it has a check next to it, then
follow the instructions in Precise Polar Alignment,
page 30. You will require the use of an illuminated
reticle crosshair eyepiece* to complete the task. Once
finished, follow the steps below for a permanently
mounted LX200 section to access the Object Library.
d. The Permanently Mounted, Polar Aligned LX200:
For those who will permanently mount the LX200 in an
observatory, or wish to use the already polar aligned
telescope for several nights in succession, it is
recommended that a high precision polar alignment
be made with one of the methods described above.
Once done, however, you need not bother yourself to
go through a polar alignment routine on successive
nights (provided that you do not move the instrument on
the pier) to access the Object Library and enjoy near
perfect tracking.
To bypass the polar alignment sequence, follow the
steps outlined below:
• Return to the POLAR menu option and place a check
next to it by pressing the ENTER key.
• Then directly enter the catalog number of an object that
you are familiar with in the sky by pressing the M,
STAR, or CNGC key (see APPENDIX D, page 34, for
information on the Object Library) and press the ENTER
key again.
• Manually center the familiar object in the eyepiece of
the telescope.
• Press and hold the ENTER key until the display reads
"Coordinates matched."
You have now synchronized the Object Library and the
LX200 will correctly access every other object in the
sky.
e. LAND: The LAND menu option transforms the ALTAZ
(Altazimuth) mounted LX200 into an electric slewing
spotting scope. In this mode, continuous tracking is
canceled and all of the celestial modes and menus are
non-functional, showing lower case lettering in the
displays and a beep tone if you try to enter one of them.
The LX200 will slew at any one of the four speeds of
SLEW, FIND, CNTR, and GUIDE as activated by
pressing the appropriately marked keys on the left
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