A telescope gives magnified views of the Earth and sky. As such, its field of view is very narrow. Pointing a scope at a distant object on the ground or a small, faint object in the sky can be difficult.
This is where a small telescope or another kind of pointing device mounted on the side of a scope can be a great help. Like the riflescope on a rifle, the pointer is aimed parallel to the main telescope and provides a low-power view that is easy to point at the target.
Many Celestron telescopes use StarPointers, a type of pointer called a red dot finder. It has a brightness-adjustable red LED or LED fiber-optic light source that is reflected off a curved transparent surface that allows both a direct view of the sky and the red dot of the LED to be seen at the same time. It has no magnification and works by superimposing a tiny brilliant red dot on top of your target.
To adjust your StarPointer:
1. Sight in the distance a building or object (half-mile away) in daytime.
2. Once you have trained your scope on a distant object and centered it in the scope’s eyepiece, position your eye about 6-8 inches back from the StarPointer and center it behind the StarPointer. (Some models have concentric rings to help you do this.)
3. Turn the thumbscrews until the red dot is atop the same object you have already centered in your eyepiece.
Now your StarPointer can be used to successfully aim the main scope. Check it right away by pointing it to another object using the StarPointer and verify that it is in the center of your scope’s eyepiece.