Bushnell 4.5" Reflector Altazimuth Short Tube Telescope - 786114

The finderscope is a small wide field of view telescope mounted alongside the main bushnell 4.5 telescope and is used to search for the target and aim the main telescope at it. But before you can use the finderscope, you will need to line it up with the telescope. This procedure will become easier with practice.

1. Install the lowest power eyepiece (25mm) into the eyepiece tube. Pick out an easily recognized, unmoving object no closer than a thousand yards away. Aim your bushnell reflector telescope toward your object until its image is centered in the eyepiece. Lock all the knobs on the mount so the reflector telescope will not move.
2. Look through the finderscope. If the object you lined up in the Altaz Short Tube Telescope is not visible, adjust the two adjustment screws and move the finderscope around until you see it.
3. Recheck your reflector telescope to make certain it is still on target. If it moved, realign it and adjust your finderscope. If it hasn't, you're all set. Your finderscope is now operational.

1. Loosen the altitude locks on the sides of the bushnell 4.5" telescope tube and the silver azimuth lock on the base of the altazimuth mount, then move the telescope in the desired direction.
2. Look through the finderscope and pan the telescope until the object appears in the field of view. Once it's in the field of view, tighten the altitude and azimuth locks.

1. Once you have found an object in the bushnell 4 .5 inch telescope, turn the focus knob until the image is sharp.
2. To focus on an object that is nearer than your current target, turn the focusing knob toward the eyepiece (i.e., so that the focus tube moves away from the front of the telescope). For more distant objects, turn the focus knob in the opposite direction.
3. To achieve a truly sharp focus, never look through glass windows or across objects that produce heat waves, such as asphalt parking lots.

1. The magnification (or power) of a bushnell 4 telescope varies depending upon the focal length of the eyepiece being used and the focal length of the telescope.
2. To calculate magnification, use the following formula, in which FL = focal length.

1. First determine your targeted object. Any bright object in the night sky is a good starting point One of the favorite starting points in astronomy is the moon. This is an object sure to please any budding astronomer or experienced veteran. When you have developed proficiency at this level, other objects become good targets. Saturn, Mars, Jupiter, and Venus are good second steps to take.
2. The first thing you need to do after assembling the bushnell 120 x telescope as planned is center the desired object in the finderscope. Provided you did a reasonable job aligning the finderscope, a quick look through the main Alt Az telescope tube at low power should reveal the same image. With the lowest power eyepiece (the one with the largest number printed on it) you should be able to focus the same image that you saw through the finderscope. Avoid the temptation to move directly to the highest power. The low power eyepiece will give you a wider field of view, and brighter image thus making it very easy to find your target object. At this point with a focused image in both scopes, you've passed the first obstacle. If you don't see an image after attempting to focus it in, you might consider aligning your finderscope again. Once you pass this step, you'll will enjoy the time spent ensuring a good alignment. Every object you center in the finderscope with this bushnell will be easily found in the main telescope tube, which is important for continuing your exploration of the night sky.
3. The low power eyepieces are perfect for viewing the full moon, planets, star clusters, nebulae, and even constellations. These should build your foundation. However, for more detail, try bumping up in magnification to higher power eyepieces on some of these objects. During calm and crisp nights, the light/dark separation line on the moon (called the "Terminator") is marvelous at high power. You can see mountains, ridges and craters jump out at you due to the highlights. Similarly, you can move up to higher magnifications on the planets and nebulae. Star clusters and individual stars are best viewed through the low power no matter what.
4. The recurring astronomical theater we call the night sky is an ever-changing billboard. In other words, the same movie does not play all the time. Rather, the positions of the stars change not only hourly as they seem to rise and set, but also throughout the year. As the earth orbits the sun, our perspective on the stars changes on a yearly cycle about that orbit. The reason the sky seems to move daily just as the sun and the moon "move across our sky is that the earth is rotating about its axis. As a result you may notice that after a few minutes or a few seconds depending on what power your are viewing at, the objects in your telescope will move. At higher magnifications especially, you will notice that the moon or Jupiter will :race: right out of the field of view. To compensate, just move your telescope to "track" it in the necessary path.