Aligning the Viewfinder, Balancing the Telescope

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9.Attach the viewfinder bracket (7) to the telescope using the 2 thumbscrews provided. These thumbscrews are pre-threaded into the telescope at the viewfinder location. The thumbscrews fit through the 2 holes at the base of the viewfinder bracket and thread into the main optical tube.

10.Insert the diagonal mirror (5) into the focuser drawtube (25) and the 25mm eyepiece (6) into the diagonal mirror. Secure each in place with a moderate tightening of the respective thumbscrews.

The telescope is now completely assembled. Before it can be affectively used, however, the viewfinder (8) must be aligned with the main telescope.

ALIGNING THE VIEWFINDER

The wide field of view provided by the 5 x 24mm viewfinder (8) permits easy object sighting prior to observation in the higher-power main telescope. To align the viewfinder, follow this procedure:

1.First remove the front lens dust cap (33) from the dew shield/lens shade (29). Then using the lowest power (25mm) eyepiece, point the main telescope at some well defined land target (e.g. the top of a telephone pole) at least 200 yards distant.

2.Look through the viewfinder (8) and tighten or loosen, as appropriate, the viewfinder’s 6 collimation (alignment) screws (9) located on the finderscope bracket (7), until the cross hairs of the viewfinder are precisely centered on the same object already centered in the main instrument’s field of view. Hint: center the front of the viewfinder in the bracket using the 3 front ring thumbscrews, then make final object centering adjustments with the back ring 3 thumbscrews.

3.With this alignment accomplished, objects located first in the wide-field viewfinder will then be centered in the main telescope’s field of view. Focusing of objects in the viewfinder is accomplished by turning the threaded eyepiece of the viewfinder. (Note: The viewfinder presents an image which is upside- down; this is customary in all astronomical viewfinders).

BALANCING THE TELESCOPE

In order for the telescope to move smoothly on its mechanical axes, it must first be balanced as follows:

Note: If the counterweight is positioned as recommended on the previous page— the telescope is already approximately balanced.

1.Loosen the Right Ascension lock knob (14). With the R.A. lock loosened, the telescope mount will turn freely about the polar axis (15). Rotate the telescope about the polar axis so that the counterweight shaft (17) is parallel to the ground (horizontal).

2.Loosen the counterweight’s locking thumb screw and slide the counterweight (18) along the shaft (17) until the telescope remains in any given position without tending to drift down in either rotational direction about the polar axis. Then retighten the counterweight lock screw (20), locking the counterweight in position.

The telescope is now balanced.

UNDERSTANDING CELESTIAL MOVEMENTS AND COORDINATES

Understanding where to locate celestial objects, and how those objects move across the sky is fundamental to enjoying the hobby of astronomy. Most amateur astronomers adopt the simple practice of “star-hopping” to locate celestial objects by using star charts or astronomical software which identify bright stars and star patterns (constellations) that serve as “road maps” and “landmarks” in the sky. These visual reference points guide amateur astronomers in their search for astronomical objects. And, while star-hopping is the preferred technique, a discussion of using setting circles for locating objects is desirable since your telescope is provided with this feature. However, be advised, compared to star-hopping, object location by use of setting circles requires a greater investment in time and patience to achieve a more precise alignment of the telescope’s polar axis to the celestial pole. For this reason, in part, star-hopping is popular because it is the faster, easier way to become initiated in the hobby.

Understanding how astronomical objects move: Due to the Earth’s rotation, celestial bodies appear to move from East to West in a curved path through the skies. The path they follow is known as their line of