User manual MEADE 883 TRIPOD

[. . . ] Grasp two of the tripod legs, leaving the full weight of the tripod on the third leg. Gently pull the legs apart to a full open position. Attaching the Accessory Tray Remove the round accessory tray (7, Fig. Remove the black, star-shaped lock knob from the threaded rod on the bottom of the accessory tray. [. . . ] 1). 1 3 4 5 2 1 12 11 10 9 1. 12. Mounting Slots Mounting Plate Latitude Scale Fine Latitude Adjustment Knob Bubble Level Height Adjustment Knob Accessory Tray Extension Strut System North-Pointing Tripod Leg (marked "N" at position of arrow) Fine Azimuth Adjustment Knobs Latitude Lock Knob Latitude Lock Lever (opposite side) ALT/AZ ALIGNMENT Alt/Az alignment (Fig. 3) is best used for terrestrial (land) viewing and for casual celestial observation. The telescope's manual slow-motion controls (ETX-90RA) or the Electronic Controller arrow keys (ETX-90EC and ETX-125EC) are used to keep the object within the field of view. NOTE: Fully automatic tracking of celestial objects can be accomplished in the Alt/Az configuration using the optional #497 Autostar Computer Controller with the ETX-90EC and ETX­125EC. The ETX-90RA must be polar-aligned to automatically track celestial objects (see POLAR ALIGNMENT). In Alt/Az viewing applications, the three legs of the #883 Deluxe Field Tripod may be positioned in an arbitrary orientation. The telescope mounting, however, should be placed in a horizontal position by turning the fine latitude adjustment knob (4, Fig. 1) reads 90°, unlocking and re-locking the latitude lock knob (11, Fig. NOTE: The ETX-90RA motor drive should be turned off in terrestrial applications. 7 6 Fig. 1: #883 Deluxe Field Tripod. ALT/AZ: Tripod head locked at 90° Little Dipper Polaris POLAR: Tripod head locked at observer's latitude Big Dipper Fig. 4: Locating Polaris. Cassiopeia By following the above procedure, the telescope is polaraligned for most celestial observing applications. Approximate polar alignment is sufficient in the great majority of these applications. Important Note: For almost all astronomical observing requirements, approximate settings of the telescope's latitude and polar axis are acceptable!Do not allow undue attention to precise polar alignment of the telescope to interfere with your basic enjoyment of the instrument. Using the North Star (Polaris) to find North will aid in polar alignment. Polaris can be found in relation to the Big Dipper by projecting a line from the so-called "pointer stars" of the Big Dipper (Fig. For southern hemisphere alignment, locate south by using the faint star Sigma Octans (the South Star). Fig. 3: Examples of Alt/Az (left) and polar mounting (right) of an ETX-90EC to the #883 Deluxe Field Tripod. POLAR ALIGNMENT Polar alignment (Fig. 3) is the process of lining up the telescope's polar axis with the North Celestial Pole (or South Celestial Pole if observing from the southern hemisphere). With a polar-aligned telescope, tracking celestial objects is possible by simply turning on the drive motor in the base of the telescope. The motor counteracts the Earth's rotation, keeping objects in the field of view. [. . . ] Once the desired latitude has been set, tighten the lock nut until it is flush against the mount. Tighten the latitude lock knob (11, Fig. NOTE: The fine azimuth adjustment knobs (9, Fig. 1), which move the telescope horizontally without moving the tripod itself, may be used to aid in the alignment procedure. 2. 2. NOTE: Depending on the accuracy of the alignment procedure, it may be necessary to use the R. A. [. . . ]