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Fig. 14: Drive Motor Housing. (1) Dust Cover; (2) R.A. Setting Circle; (3) Set Collar; (4) Battery Compartment; (5) 3 Knurled Head Screws.
6.Remove the jumper from one prong and slide it onto both prongs. The telescope will now track in an easterly direction for southern hemisphere operations.
7.To return the telescope to northern hemisphere operations, pull the jumper off both prongs and store it on one of the prongs.
8.When replacing the dust cover, be careful of keeping the wires away from the gear system.
Setting Circles
Setting circles included with the 16" Starfinder permit the location of faint celestial objects not easily found by direct visual observation. The R.A. circle (1), Fig. 13, is located at the end of the polar housing, on the side of the Control Panel. The Declination (Dec) circle (2), Fig. 13, is located at the end of the Declination Housing, just above the counterweight shaft. With the telescope pointed at the North Celestial Pole, the Dec circle should read 90° (understood to mean +90°). Objects located below the
if the telescope was
If the object is not immediately visible through the telescope, try searching the adjacent sky area. Because of its much wider field, the viewfinder may be of significant assistance in locating and centering objects, after the setting circles have been used to locate the approximate position of the object.
Pinpoint application of the setting circles requires that the telescope be precisely aligned with the pole.
The setting circles may also be utilized in the absence of a power source for the motor drive. In this case, however, it is necessary to manually reset the R.A. of the object being observed just before moving the telescope to the next object.
Observing Tips
To enjoy the 16" Starfinder telescope to its fullest potential, follow these recommendations:
1.Let the telescope "cool down" to the outside temperature before attempting to make serious observations. After removing the telescope from a warm house, the telescope's optics need about 30 to 45 minutes to adjust to the outside temperature before they will perform well.
2.Avoid setting up the telescope inside a room and observing through an open window (or, worse, a closed window!). In such a case air currents caused by differences in indoor/outdoor temperatures make quality astronomical optical performance impossible.
Note: A practical exception to the above rule is the case where the Starfinder is, for example, set up in a living room or den for observing an outdoor terrestrial scene or view through a closed window. At low powers (up to about 60X) the telescope will perform reasonably well in this application, but the observer should understand clearly that optical performance under these conditions can not approach the performance that will be realized if the telescope were instead set up outside.
3.As discussed above, avoid "overpowering" the telescope. If the terrestrial or astronomical image becomes fuzzy at high powers, drop down to a lower power. Image degradation at high powers is not due to any fault of the telescope but is caused by heat waves and turbulence in the earth's atmosphere. Astronomical observations at high powers (i.e., above about 200X) should be undertaken only when the atmosphere is very steady, as confirmed by an absence of "twinkling" in star images.
Note that the R.A. circle is
To use the setting circles to locate an object not easily found by direct visual observation:
With the telescope aligned to the pole, center an object of known R.A. in the telescopic field. Then turn the R.A. circle, which can be rotated manually, until the R.A. coordinate of the object is correctly indicated by the R.A. pointer. As long as the telescope's motor drive remains "ON," the R.A. pointer will then correctly indicate the R.A. of any object at which the telescope is pointed throughout the duration of the observing session.
To locate a particular object, first look up the celestial coordinates (R.A. and Dec) of the object in a star atlas. Then, turn the telescope to read the correct R.A. of the desired object. Turn the telescope in Declination to read the correct Declination of the object. If the procedure has been followed carefully, and
4.Try not to touch the eyepiece when observing through the telescope. Vibrations in your hand are immediately transferred to the telescopic image.
5.If you wear eyeglasses and do not suffer from astigmatism, take your glasses off when using the telescope; the telescope's magnification compensates for near- or farsightedness. Observers with astigmatism should, however, wear their glasses, since the telescope can not compensate for this eye defect.
6.Allow your eyes to become "dark adapted" before attempting serious astronomical observations through the telescope. Night adaptation normally requires about 10 to 15 minutes.
7.As you use your Starfinder more and more for astronomical observing, you will find that you are seeing finer and finer detail — on the surface of Jupiter, for example. Observing through a fine optical instrument is to some degree an acquired skill. Celestial observing becomes increasingly rewarding as your eye becomes better trained in the detection of subtle variations of color, contrast, and resolution.