Bushnell Model 78-9570 Telescope User Manual


 
ANSWERS TO COMMONLY ASKED QUESTIONS
1. The image I see in the telescope is upside down
and reversed from right to left?
An upside-down and reversed image is a
common characteristic of most astronomical
telescopes. Since telescopes are used for
astronomical viewing orientation is not important.
However, as described above, the T-18 erecting
lens can be used to provide normal images.
2. How do I determine the power my telescope? The power of your telescope can be determined
by dividing the focal length of the objective lens
by the focal length of the eyepiece. The
eyepiece focal length is the number printed on
the eyepiece. (For example: 1000 ÷ 25 = 40X)
3. Where do I find the Telescope Focal Length The telescope focal length is the same focal
length as the objective focal length. For this
telescope it is 910mm. Telescope focal lengths
range from 600mm to 910mm on Bushnell
telescopes.
4. What can I see with my telescope? Telescopes with power ranging from 25X to 50X
can be used to view Star Clusters and Nebulae.
90X to 120X telescopes can view galaxies. Most
planets can be seen at 150X and higher.
5. What do the numbers on the eyepiece mean? The numbers on the eyepiece represents the
“focal Length” of the eyepiece.
TROUBLESHOOTING GUIDE
If after you have set-up your new telescope you are unable to see any objects, use this Quick
Reference guide to help you to understand the cause of the problem and quickly determine a remedy
1. I’ve completed the set-up yet I cannot see anything Check to see if objective lens cover has been
removed.
Try to view an object that is 200 or more yards
away.
If there is more than one eyepiece included with
the telescope, use the lowest power (highest
number) eyepiece to begin viewing.
Use the Rack & Pinion Focusing Mechanism (3) to
bring the object you are trying to view into focus