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Eyepiece: An eyepiece is a system made for your eye and comprised of one or more lenses. In an eyepiece, the clear
image that is generated in the focal point of a lens is captured and magnified still more.
Magnification: The magnification corresponds to the difference between observation with the naked eye and
observation through a magnifying device like a telescope. If a telescope configuration has a magnification of 30x, then
an object viewed through the telescope will appear 30 times larger than it would with the naked eye. To calculate the
magnification of your telescope setup, divide the focal length of the telescope tube by the focal length of the eyepiece.
Using/Aligning the Red Dot Viewfinder:
The viewfinder is powered by a CR-1620 battery that is included. Before using the viewfinder for the first time,
remember to remove the plastic insulator that is blocking the battery from connecting.
For The Viewfinder To Be Effective, It Must Be Aligned. To do this:
• Insert the 26 mm eyepiece into the diagonal and
power on the viewfinder by sliding the switch on
its right side to an “On” position.
• Point the eyepiece at an easy to identify target
like a telephone pole that is approximately 200
yards away. Center the object in the eyepiece.
Lock the telescope into place by tightening the
panhandle.
• Without moving the telescope, position the
red dot using the two adjustment screws so
that it shares the same view as the one in
your eyepiece. The front screw will move the
viewfinder up and down, and the other will move
it side to side. Your viewfinder is now aligned.
Note: To preserve battery life, don’t forget to turn off
the viewfinder after use.
Using your telescope:
After you have aligned your viewfinder, you are
ready to start observing! Put the 26 mm eyepiece
into the diagonal to get the widest field of view. This
wider field of view will make it easier to locate and track objects. Use the panhandle to move the scope up, down and
side to side until your target comes into view in the eyepiece. It is important to remember that the rotation of the Earth
means objects will move out of your eyepiece fairly quickly. Once you have found and focused on your desired target,
you can track it as it journeys across the night sky using the panhandle.
For a closer look at an object, you can insert the 9.7 mm eyepiece. The magnification will increase from 26.9x to 72x.
For a more closer look at an object, you can insert the 2x Barlow lens. The magnification will increase to 52x for the
26 mm eyepiece and 144x for the 9.7 mm eyepiece.
Cleaning:
Your telescope is a precision optical device and keeping the optics free of dust and dirt is crucial for optimal
performance. To clean the lenses (objective and eyepiece) use only a photo-grade soft brush or a lint-free cloth, like a
microfiber cloth. Do not press down too hard while cleaning, as this might scratch the lens. Ask your parents to help if
your telescope is really dirty. f necessary, the cleaning cloth can be moistened with an optical glass cleaning fluid and
the lens wiped clean using very little pressure. Do not use harsh detergents!
Make sure your telescope is always protected against dust and dirt.
After use, leave it in a warm room to dry off before storing.
CR1620
BATTERY
3V
The Red Dot Viewfinder is
powered by a battery type CR-1620
(3V); if a replacement is necessary,
remove cap (Fig. 1) by twisting
counter clockwise (Fig. 2) remove old
battery and insert new battery in place
with the positive (+) side showing.
Replace cap and tighten clockwise.
Fig. 1
Fig. 2
Red Dot Viewfinder
(back view)
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