Tele Vue 60 - Manual (Page 4)

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1.3 FOCUSING
A) Rotate the FINE FOCUS RING so it is set halfway through its travel. This will
permit the greatest amount of +/- fi ne focus travel.
B) Point the scope towards an object you'd like to view.
C) Grasp the rubber grip ring on the FINE FOCUS RING and adjust the DRAW
TUBE TENSION SCREW on top of the telescope body so that the push-pull action is loose
enough to allow easy motion, but not so loose that the COARSE FOCUS DRAW TUBE
slips backwards on its own.
D) Pull the COARSE FOCUS DRAW TUBE out until focus has roughly been
achieved and lightly tighten the DRAW TUBE TENSION SCREW. (CAUTION: DO NOT
REPEATEDLY PUSH OR PULL THE DRAW TUBE QUICKLY. THIS PUMPING AC-
TION CAN DRAW DUST INTO THE TELESCOPE.)
E) Now, rotate the FINE FOCUS RING until your object is in sharp focus.
1.4 BALANCE
The balance of the telescope may change depending on the eyepiece or camera
used. To adjust the balance:
A) Loosen the BALANCE BAR LOCK SCREW.
B) Holding the TELESCOPE BODY, slide the entire telescope fore or aft until
balance is reached.
C) Tighten the BALANCE BAR LOCK SCREW only enough to hold the scope
in position. Do not overtighten.
2. TELESCOPE & SPOTTING SCOPE BASICS
Many people who use telescopes and spotting scopes are curious about just
how they work. What is magnifi cation power, and how does it work? It is very simple.
When we wish to inspect a distant object more critically, we will intuitively bring it (or
ourselves) closer. The “enlargement” from this closer proximity permits us to more easily
see smaller details.
A telescope’s objective lens forms an image of an object as if it were closer to the
observer, like a telephoto camera lens. However, this real “image” is so small that, although
enlarged, it is diffi cult to see any of its fi ne detail. Therefore, a “magnifi er,” called an
eyepiece, is used to look at a portion of the “image” in greater detail. The magnifi cation,
therefore, depends on the relationship between the focal lengths of the objective (to form
the image) and the eyepiece (to enlarge the image). To fi gure out the magnifi cation factor,
divide the telescope's focal length by the eyepiece focal length. For example, the Tele
Vue-60’s 360mm objective used with an 20mm eyepiece yields 18 power. (360÷20=18x)
The combined qualities of the objective lens and the eyepiece (as well as anything
else in the light path between them, such as prisms or mirrors—see below) help determine
the quality of the magnifi ed view. One of the secrets of the Tele Vue-60’s extraordinary
optical performance is its partnership with the family of Tele Vue eyepieces.
For terrestrial use, prisms are often employed to provide a correct presentation of
the objective’s image, as well as folding the light path to make the instrument more compact
and/or easier to use. In most terrestrial spotting scopes, the prisms are built in, and are
not removable. Most astronomical telescopes have no prisms, since the image erecting
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60 as you would normally.
With the Tele Vue-60 on your camera, you have a 360mm, f/6 telephoto lens! This
is about 7x the magnifi cation of a 50mm lens. The Tele Vue-60’s fast f/6 performance is
great with DSLR's with APS format, ideal for high resolution nature photography.
B) AFOCAL PHOTOGRAPHY — Tele Vue's afocal camera adapters permit
your digital camera to zoom into your image! Adapters are available for digital cameras
with 28mm, 37mm and 49mm fi lter threads. If your camera lens (or lens cover tube) has
a different thread, you can usually fi nd a step-up or step-down ring to mate with one of the
Tele Vue thread sizes of 28/37/49mm. Best results occur with long eye-relief eyepieces
such as 32mm Plössl.
7. ACCESSORIES
A) CARRY BAG — The Tele Vue-60 is supplied standard with a GORE-TEX ®
bag which has been sized to fi t the Tele Vue-60 optical tube plus diagonal and eyepiece.
Always pull the draw string taut and slide the string lock down against the bag when the
scope is in place.
B) SOFT CARRY CASE — The optional carry case measures just 13" long x 9"
wide x 4" deep, and holds the Tele Vue-60 optical tube, diagonal or prism of your choice,
plus three eyepieces in custom die-cut foam. The Nylon soft case is padded and comes
with both a carry handle and shoulder strap.
When packing up for the evening, always install the front lens
cover and close Tele Vue-60 in the optional carry case or its bag
box before bringing the telescope inside. Do not open the bag
or box until it reaches room temperature. This will prevent dew
from forming on the telescope. If excessive dew builds up on the
telescope body, wipe it off with a soft cloth.
8. CARING FOR THE TELE VUE-60
The Tele Vue-60 requires no special care. Treat it as you would any fi ne camera
lens. Use the lens cap when the telescope is not in use or being stored.
As stated earlier, do not pump the draw tube in and out quickly. This can cause
dust or airborne grit to be drawn into the telescope.
If you leave your scope idle in dewy conditions it is always a good idea to tilt the
telescope slightly up. If dew forms on the lens during cold weather, it is best to use an
electric hair dryer (on the lowest setting) to gently warm it away. A few specks of dust will
have no effect on the quality of the image, and may be gently blown off with a squeeze bulb.
Do not use compressed air cans to blow dust off any optical surfaces.
Fingerprints, however should be cleaned off. Though the anti-refl ection coatings
are durable, they can be scratched. The simplest cleaning method is to moisten a very soft,
lint-free tissue, cloth, “Q-Tip” or surgical cotton with a lens or glass cleaner and gently
whisk away the stain. Do not apply any solutions directly to the glass surfaces. After every