Go Out:  Look Up!

A Guide to the Sky, Telescopes, and Telescope Programs

Home How a Scope Works Using a Scope Note to Parents Aiming a Scope Using a Finder Eyepieces Using a Zoom Fun Equipment


Aiming a Dobsonian Scope

This is taken from the Starblast manual:

Simply take hold of the navigation knob and push or pull it to move the telescope and base in the desired direction.

Both the altitude and azimuth motions can be made simultaneously and in a continuous manner for easy aiming. This way you can point to any position in the night sky, from horizon to horizon.

You may find it convenient to hold one hand on one of the carrying handles to help in leveraging the base while moving and aiming the telescope.

When aiming the telescope in altitude (up or down), you may find the optical tube assembly is either too hard to move or does not stay in place. Use the altitude tension knob to adjust the friction on the altitude axis until you achieve the desired amount. Ideally, you should adjust the tension on the altitude axis so that the amount of friction roughly matches that of the azimuth axis (which is not adjustable).

To "acquire a target":

First, you have to know where your target is.  If it's bright enough to see with the naked eye, that is fairly easy.  If it is not visible to the naked eye, you need to know it's approximate location and aim your scope there.  A finder telescope should brighten the object so that it should show up in the finder (if it's pointed in the right place.  If not you'll have to manually push the scope around in the general area, hoping to find it). 

To show up in the finder, the telescope needs to be pointed to within about 5 degrees of the target.  If you place your eye by the bottom of the scope and sight along it, you can generally get the scope pointed close.  Then, a finder telescope should show the object in its view. 

Center the object in the crosshairs of the finder.  Note that the image is probably reversed and backwards: it may take practice to center the object.

Once centered, look through the telescope eyepiece.  The wider the eyepiece (lower magnification) the more likely the target is to be in the field of view.  Zoom eyepieces can be set wide to find and center the object and then zoomed in for higher magnitude observation.

For further information on using a finder scope click here.

Questions or comments? Email:Jeff Martin