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Let’s say that you have obtained a 13mm eyepiece. You can tell that what the focal length of your eyepiece is as it is always printed on the side of an eyepiece. Divide: 700 ÷ 13, which equals 53.8. Round this off to the nearest whole number and your new eyepiece magnifies objects 54 times.
A great optional accessory is a Barlow lens If you use a Barlow lens with one of your eyepieces, it doubles the magnification
of your eyepiece. Other types of Barlows can triple or further increase the power of an eyepiece. To find out how much the magnification is when you use a Barlow, multiply your eyepiece’s magnification by two.
Eyepiece’s magnification x 2
=
Magnification with a 2X Barlow lens
Your 25mm
It’s worth repeating: Keep in mind that a bright, clear, but smaller image is more
interesting than a larger, dimmer, fuzzy one. Using too high a power eyepiece is one of the most common mistakes made by new astronomers. So don’t think that higher magnification is necessarily
TAKING CARE OF YOUR TELESCOPE
Your telescope is a precision optical instrument designed for a lifetime of rewarding viewing. It will rarely, if ever, require factory servicing or maintenance. Follow these guidelines to keep your telescope in the best condition:
•Avoid cleaning the telescope’s lenses. A little dust on the front surface of the telescope’s correcting lens will not cause loss of image quality.
•When absolutely necessary, dust on the front lens should be removed with very gentle strokes of a camel hair brush or blown off with an ear syringe (available at most pharmacies).
•Fingerprints and organic materials on the front lens may be removed with a solution
of 3 parts distilled water to 1 part isopropyl alcohol. You may also add 13 1 drop of biodegradable dishwashing soap per pint of solution. Use soft, white facial tissues and make short, gentle strokes. Change tissues often.
CAUTION: Do not use scented or lotioned tissues or damage could result to the optics. DO NOT use a commercial photographic lens cleaner.
OPTIONAL ACCESSORIES
#928 45° Erecting Prism (1.25 O.D.): Correctly orients the telescopic image
JOIN AN ASTRONOMY CLUB, ATTEND A STAR PARTY
One of the best ways to increase your knowledge of astronomy is to join an astronomy club. Check your local newspaper, school, library, or telescope dealer/ store to find out if there’s a club in your area.
Many groups also hold regularly scheduled Star Parties at which you can check out and observe with many different telescopes and other pieces of astronomical equipment. Magazines such as Sky and Telescope and Astronomy print schedules for many popular Star Parties around the United States and Canada.
Looking at or near the Sun will cause irreversible damage to your eye. Do not point this telescope at or near the Sun. Do not look through the telescope as it is moving.
