CELESTRON 71240 EclipSmart 20×50 Solar Binoculars Instruction Manual
- June 9, 2024
- Celestron
Table of Contents
71240 EclipSmart 20×50 Solar Binoculars
Instruction Manual
SOLAR BinocularS
INSTRUCTION MANUAL
71240 EclipSmart 20×50 Solar Binoculars
Conforms to and meets the Transmission
Requirements of ISO 12312-2, Filters for Direct Observation of the Sun
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.
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.
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.
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.
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.
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.
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 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. 
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.
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.
CARE AND CLEANING
Binoculars do not need routine maintenance other than making sure that the
objective lenses and eyepieces are clean. If repairs become necessary,
please contact Celestron’s customer service department.
Collimation (optical alignment) is the biggest concern with binoculars. If
your binoculars are roughly handled or dropped, there is a good chance that
they could be knocked out of collimation, requiring service from Celestron’s
repair department. When you are not using your binocular, always store it in
the case provided.
Avoid touching your binocular’s glass surfaces. If fingerprints (which contain
mild acid) get on them, they should be cleaned as soon as possible to avoid
damaging the coatings.
To clean the optical surfaces, we recommend a lens/optics cleaning kit
available at most photo or optical shops. Follow the kit’s instructions
closely. If your lenses have a lot of dust or dirt accumulated, brush it off
gently with a camel’s hair brush or use a can of pressurized air before using
the cleaning kit. You could also use the Celestron Lens Cleaning Kit or
LensPen Optics Cleaning Tool made especially for cleaning binoculars.
NEVER ATTEMPT TO CLEAN YOUR BINOCULARS INTERNALLY OR TRY TO DISASSEMBLE THEM!
SOLAR BINOCULARS
PROBLEMS OR REPAIR
If warranty problems arise or repairs are necessary, contact the Celestron
technical support department if you live in the U.S.A. or Canada. If you live
elsewhere, please contact the Celestron dealer you purchased the binoculars
from or the Celestron distributor in your country (listings on the Celestron
website).
IMPORTANT: Celestron EclipSmart binoculars are specially designed with
built-in Solar Safe filters. If you notice any damage to these filters, do not
use them for solar observation and contact Celestron’s customer service
department.
WARRANTY
Your binocular has the Limited Lifetime Warranty for U.S.A. and Canadian
customers. For complete details of eligibility and for warranty information on
customers in other countries, visit the Celestron website:
www.celestron.com
This product is designed and intended for use by those 14 years of age and
older. Product design and specifications are subject to change without prior
notification.
©2022 Celestron.
Celestron and Symbol are trademarks of Celestron, LLC.
All rights reserved. Celestron.com
Torrance, CA 90503 USA
71237/71238/71239/71240
07-22
Printed in China
References
- Celestron - Telescopes, Telescope Accessories, Outdoor and Scientific Products
- Celestron - Telescopes, Telescope Accessories, Outdoor and Scientific Products