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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