Bushnell 78-9970 Telescope User Manual


 
11
GETTING STARTED WITH YOUR NEW TELESCOPE
2. After setting up the telescope and selecting something to view, center the desired object
in the finderscope. Provided you did a reasonable job aligning the finderscope, a quick
look through the main 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 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 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, not the same movie plays 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 you 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 the fine adjustment controls
on your telescope to “track” it in the necessary path.