Celestron 71237 User manual

INSTRUCTION MANUAL ENGLISH
SOLAR BinocularS
10x25
71237
10x42
71238
12x50
71239
20x50
71240

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SOLAR BINOCULARS
CELESTRON ECLIPSMART BINOCULARS
Thank you for purchasing a Celestron EclipSmart binocular. We are confident it will
bring you many years of enjoyable solar observation. This EclipSmart binocular is a
very specialized optical instrument, so please read these instructions before using it.
IMPORTANT SAFETY NOTE: If done incorrectly, direct observation of the Sun can be
harmful to your vision. Never look directly at the Sun without using equipment specially
designed and tested for that purpose. Celestron’s EclipSmart binoculars meet and
conform to the ISO 12312-2 International Standard for safe direct visual observation of
the Sun. EclipSmart binoculars should not be used for solar observation if the objective
filters have been damaged, tampered with, or removed.

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SOLAR BINOCULARS
SET-UP AND USE OF YOUR CELESTRON ECLIPSMART BINOCULAR
Because of its built-in solar filters, you won’t be able to see anything other than
the Sun through an EclipSmart binocular. If you do see something other than the
Sun through these binoculars, discontinue use immediately and contact Celestron’s
customer service department.
SET-UP
1. Adjusting the Interpupillary Distance (IPD)
Since the distance between the eyes (specifically,
the distance between the centers of the pupils)
varies among individuals, you’ll need to adjust the
distance between your binocular’s two eyepieces to
align with your eyes. To do this, lift the binoculars up
to your eyes (using both hands) and move the two
halves of the binoculars by flexing the hinge until
both eyes seem to be fully covered by the eyepieces.

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SOLAR BINOCULARS
2. Adjusting Diopter
EclipSmart binoculars feature a diopter
compensation adjustment mechanism on the right
eyepiece for sharpest focus. If you do not wish to
make an initial diopter correction adjustment, simply
check to make sure the indicator on the right eyepiece
is set to the “zero” mark prior to use. You can find
a detailed explanation of how to set the diopter
compensation later in this manual in the “Use”
section, item 3.
3. Positioning the Rubber Eyecups
Leave the rubber eyecups up if you do not wear
eyeglasses, but fold them down if you do wear
eyeglasses to obtain the maximum field of view.
Diopter
Adjustment Ring

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SOLAR BINOCULARS
1. Positioning the Binocular
Take up the binocular in both hands and with your view downward toward the ground
in front of you, turn your body so that you are facing the direction of the Sun. Place
the binocular eyecups in front of your eyes so that they are both completely covered.
Then, keeping the eyecups of the binocular squarely in front of your eyes, raise your
head until the solar disk appears in the binocular’s field of view. If the solar disk is
not immediately apparent in the field of view, slowly scan with the binocular until it
becomes apparent. NEVER REMOVE THE ECLIPSMART BINOCULAR FROM IN
FRONT OF YOUR EYES WHILE YOUR GAZE IS DIRECTED TOWARD THE SUN.
USE
Using EclipSmart binoculars is similar to using a standard binocular—with one
important difference. To ensure your eyes are always protected, position your eyes
behind the eyecups BEFORE raising them into position to view the Sun.

Focus Dial
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SOLAR BINOCULARS
2. Adjusting Focus
To focus your EclipSmart binocular, simply turn the large dial
located between the two barrels until you see a sharp image
of the solar disk.
3. Adjusting Diopter
As solar observation with binoculars does not require the level
of fine detail that other types of astronomical or terrestrial
observation does, most users will not need to make any
adjustments to the diopter compensation of the binocular
other than setting it to the zero (“0”) mark. However, if you would like to fine tune the
diopter for your unique eyesight, follow these steps, making sure that you never allow
yourself to look at the Sun without both eyepieces of the binocular fully in front of
your eyes at all times. Begin with the EclipSmart binocular safely positioned in front
of your eyes and the solar disk in view, without moving the binocular away from your
eyes:
A. Keep both eyes open and use one hand to cover the right objective lens. Adjust
the center focus dial until the image you see through the left eyepiece is sharp.
Do not touch the center focus dial again until this process is complete.

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SOLAR BINOCULARS
B. Move your hand away from the right objective lens and cover the left objective lens.
If the image you see through the right eyepiece is sharp, you are finished. If it is not,
adjust the diopter correction dial on the right eyepiece until it is.
C. Move your hand away from the left objective lens and assess the image as seen
through both eyepieces simultaneously. The image should now be sharp and
satisfying to view.
OBSERVING THE SUN
SOLAR ECLIPSES
Solar eclipses occur somewhere on Earth at least twice a year. There are two kinds of
eclipses—partial and total.
A partial solar eclipse happens when the Moon passes directly between the Earth and
the Sun and the Moon blocks part of the Sun’s light. If the Moon happens to be near the
far point of its orbit from Earth, a very special form of a partial eclipse occurs, called an

PARTIAL ECLIPSE ANNULAR ECLIPSE TOTAL ECLIPSE
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SOLAR BINOCULARS
annular eclipse. In an annular eclipse, the Moon will block out most of the Sun’s disk,
but leaves a small ring (or annulus) of sunlight surrounding the Moon. A total eclipse
occurs when the moon is close enough to the Earth in its orbit so that it blocks the entire
disk of the Sun from view. The partial phases of a total solar eclipse leading up to totality
are incredible to watch. The Moon will first appear as a small dark dent in the edge of
the Sun, growing to a large bite. If you are in the path of totality, the Sun will eventually
become a thin crescent and then disappear completely. For a couple of minutes, daytime
turns to deep twilight and bright stars and planets are visible in the daytime sky. After totality,
the process reverses itself as the Sun re-emerges from behind the Moon. It is a sight that
should not be missed.

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SOLAR BINOCULARS
Sunspots
Sunspots are dark spots that appear on the photosphere, or visible “surface” of the Sun.
They usually have a dark core, called the umbra, surrounded by a lighter border, called
the penumbra. They form when large disturbances in the Sun’s magnetic field cool
portions of the photosphere. Sunspots are relatively cool, being only 6,000°F (3,300°C)
compared to the normal 10,000°F (5,500°C) of the rest of the photosphere. Although
these spots appear to be almost black, they are actually quite bright. If it were possible
to remove a sunspot from the Sun and put it in the night sky, it would shine brighter
than the Full Moon. They only appears to be “dark” when compared to the rest of the
photosphere.
Sunspots can be big. Very big. They can range in size from 10 to 100,000 miles (16
to 160,000 km) in diameter. To put that into perspective, the Earth is only 8,000 miles
(12,800 km) in diameter! Compare sunspot sizes to the relative size of the Earth in the
image on the next page to better grasp the immense size of the Sun and share that
WOW factor with neighbors, friends, and family.

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SOLAR BINOCULARS
Sunspots usually appear in pairs but can
also appear in very large groups. They can
last from a few days to several weeks and
can change their shape, size and number as
they slowly rotate across the face of the Sun.
It will take about two weeks for a sunspot
group to cross the Sun. Try looking at the
Sun every day and draw a picture of what you
see. At the end of the week, compare your
drawings and you’ll see how sunspots evolve.
PLANETARY TRANSIT
Planetary transits occur when the planet
Mercury or Venus passes between the Sun and Earth, allowing observers on Earth to
track the planet’s dark disk as it crosses the face of the Sun. This is an extremely rare
event, occurring only four times over the next 50 years.
1.3 MILLION EARTHS CAN
FIT INSIDE THE SUN
EARTH
JUPITER