horizontal position.
5.With one hand on the telescope optical tube, loosen the Dec. lock knob. The telescope should now be able to rotate freely about the Dec. axis. Loosen the tube ring clamps a few turns, until you can slide the telescope tube forward and back inside the rings (this can be aided by using a slight twisting motion on the optical tube while you push or pull on it) (Figure 4c).
6.Position the telescope so it remains horizontal when you carefully let go with both hands. This is the balance point (Figure 4d). Before clamping the rings tight again, rotate the telescope so the eyepiece is at a convenient angle for viewing. When you are actually observing with the tele- scope, you can adjust the eyepiece position by loosening the tube rings and rotating the optical tube.
7.Retighten the tube ring clamps.
The telescope is now balanced on both axes. Now when you loosen the lock knob on one or both axes and manually point the telescope, it should move without resistance and should not drift from where you point it.
Focusing the Telescope
With the 25mm Sirius Plössl eyepiece in the focuser, move the telescope so the front (open) end is pointing in the gen- eral direction of an object at least
If you have trouble focusing, rotate the focus knob so the drawtube is in as far as it will go. Now look through the eye- piece while slowly rotating the focus knob in the opposite direction. You should soon see the point at which focus is reached.
Do You Wear Eyeglasses?
If you wear eyeglasses, you may be able to keep them on while you observe, if your eyepieces have enough “eye relief” to allow you to see the whole field of view. You can try this by looking through the eyepiece first with your glasses on and then with them off, and see if the glasses restrict the view to only a portion of the full field. If they do, you can eas- ily observe with your glasses off by just refocusing the tele- scope the needed amount.
Aligning the Finder Scope
The finder scope (Figure 3a) must be aligned accurately with the telescope for proper use. To align it, aim the main tele- scope in the general direction of an object at least
View through finder scope and telescope
Figure 5. The view through a standard finder scope and reflector telescope is upside down. This is true for the SpaceProbe 130ST and its finder scope as well.
Now, look in the finder scope. Is the object visible? Ideally, it will be somewhere in the finder’s field of view. If it is not, some coarse adjustments of the two black nylon finder scope alignment thumb screws will be needed to get the finder scope roughly parallel to the main tube.
Note: The image in both the finder scope and the main telescope will appear
By loosening or tightening the alignment thumb screws, you change the line of sight of the finder scope. Continue making adjustments to the alignment thumb screws until the image in both the finder scope and the telescope’s eyepiece is exactly centered. Check the alignment by moving the telescope to another object and fixing the finder scope’s crosshairs on the exact point you want to look at. Then look through the telescope’s eyepiece to see if that point is centered in the field of view. If it is, the job is done. If not, make the neces- sary adjustments until the two images match up.
The finder scope alignment needs to be checked before every observing session. This can easily be done at night, before viewing through the telescope. Choose any bright star or planet, center the object in the telescope eyepiece, and then adjust the finder scope’s alignment screws until the star or planet is also centered on the finder’s crosshairs. The finder scope is an invaluable tool for locating objects in the night sky; its usage for this purpose will be discussed later, in detail.
When transporting the telescope, we recommend removing the finder scope and bracket from the tube. This is done by simply loosening the thumbscrew on the dovetail slot.
Store the finder scope and bracket in an appropriate eye- piece/accessory case.
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