Bresser National Geographic 76-700 Mode D'emploi page 16

11. Dismantling:
After an interesting and successful observation, it is recommended
that you store the entire telescope in a dry, well-aired area.
On some telescopes, the tripod and mount can easily be separated.
The adjustments to the mount will remain intact.
Don't forget to put the dust-protection caps onto the tube
opening and onto the eyepiece connection before storing. Also, you
should stow all eyepieces and optical accessories in their
corresponding receptacles.
i
NOTE!
The erecting lens is not recommended for ast-
ronomical observations. Only use the diagonal
mirror for astronomical observations. Use the
erecting lens to observe landscapes.
Notes on cleaning
Clean the eyepieces and lenses only with a soft, lint-free cloth, like a
microfibre cloth. Do not apply excess pressure to the cloth to avoid
scratching the lenses.
To remove more stubborn dirt, moisten the cleaning cloth with an
eyeglass-cleaning solution and wipe the lenses gently.
Protect the device from dust and moisture. After use, particularly in
high humidity, let the device acclimatize for a short period of time, so
that the residual moisture can dissipate before storing. Remove the
dust cover and store it in the included bag during use.
Part III – Appendix
1. Possible observation targets
The following section details several interesting and easy-to-find
celestial objects you may want to observe through your telescope.
The pictures at the end of the manual show what the objects will
look like through your telescope's eyepiece.
The moon (No. 31)
The moon is Earth's only natural satellite.
Diameter: 3,476 km
Distance: 384,400 km from Earth (average)
The moon has been known to humans since prehistoric times. It is
the second brightest object in the sky, after the sun. Because the
moon circles the Earth once per month, the angle between the Earth,
the moon and the sun is constantly changing; one sees this change
in the phases of the moon. The time between two consecutive new
moon phases is about 29.5 days (709 hours).
Constellation Orion: The Orion Nebula (M 42) (No. 32)
Right Ascension: 05 h 35
Declination: -05° 22' (Degrees : minutes)
Distance: 1,344 light years from Earth
Though it is more than 1,344 light years from Earth, the Orion Nebula
(M 42) is the brightest diffuse nebula in the sky. It is visible even with
the naked eye and a worthwhile object for telescopes of all types
and sizes. The nebula consists of a gigantic cloud of hydrogen gas
with a diameter of hundreds of light years.
Constellation Lyra: The Ring Nebula (M 57) (No. 33)
Right Ascension: 18 h 53
Declination: +33° 02' (Degrees : minutes)
Distance: 2,412 light years from Earth
The famous Ring Nebula (M57) in the Lyra constellation is often
viewed as the prototype of a planetary nebula. It is one of the mag-
nificent features of the Northern Hemisphere's summer sky. Recent
studies have show that it is probably comprised of a ring (torus) of
brightly shining material that surrounds the central star (only vis-
ible with larger telescopes), and not a gas structure in the form of a
sphere or an ellipse. If you were to look at the Ring Nebula from the
16
m (hours : minutes)
m (hours : minutes)
side, it would look like the Dumbbell Nebula (M 27). When viewed
from Earth, we are looking directly at the pole of the nebula.
Constellation Vulpecula (Little Fox):
The Dumbbell Nebula (M 27) (No. 34)
Right Ascension: 19 59 (hours : minutes)
h m
Declination: +22° 43' (Degrees : minutes)
Distance: 1,360 light years from Earth
The Dumbbell Nebula (M 27) was the first planetary nebula ever dis-
covered. On 12 July 1764, Charles Messier discovered this new and
fascinating class of objects. We see this object almost directly from
its equatorial plane. If we could see the Dumbbell Nebula from one
of its poles, we would probably see the shape of a ring, something
very similar to what we know as the Ring Nebula (M 57). In reason-
ably good weather, we can see this object well, even with low mag-
nification.
2. Troubleshooting:
Problem: Solution:
No picture Remove dust-protection cap and
sunbathe-shield from the objective
opening.
Blurred picture Adjust focus using focus ring.
No focus possible Wait for temperature to balance out.
Bad picture quality Never observe through a glass surface.
Viewing object visible Adjust finder
in the finder, but not (See Part I – 8: Construction).
through the telescope
Heaviness in the flexible Telescope and counter
handles on the axis weight are not balanced.
over the shaft
Despite using star The star diagonal prism
diagonal prism, should be vertical in
the picture is the eyepiece connection.
crooked
DISPOSAL
Dispose of the packaging materials properly,
according to their type, such as paper or card-
board. Contact your local waste-disposal service
or environmental authority for information on the
proper disposal.
Please take the current legal regulations into
account when disposing of your device. You
can get more information on the proper disposal
from your local waste-disposal service or envi-
ronmental authority.