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an hour or more. In the winter, storing the telescope outdoors
in a shed or garage greatly reduces the amount of time need-
ed for the optics to stabilize. It also is a good idea to keep the
scope covered until the Sun sets so the tube does not heat
greatly above the temperature of the outside air.

Youc an attach a small fan to the Atlas 8 EQ to make cooling
the tube faster. On the bottom of the mirror cell there are four
holes (M4x.7 thread) where a fan can be mounted.

D. Let Your  Eyes  Dark-Adapt

Do not expect to go from a lighted house into the darkness of
the outdoors at night and immediately see faint nebulas,
galaxies, and star clusters- or even very many stars, for that
matter. Your eyes take about 30 minutes to reach perhaps
80% of their full dark-adapted sensitivity. Many observers
notice improvements after several hours of total darkness. As
your eyes become dark-adapted, more stars will glimmer into
view and you will be able to see fainter details in objects you
view in your telescope. Exposing your eyes to very bright day-
light for extended periods of time can adversely affect your
night vision for days. So give yourself at least a little while to
get used to the dark before you begin observing.

To see what you are doing in the darkness, use a red-filtered
flashlight rather than a white light. Red light does not spoil
your eyes’ dark adaptation like white light does. A flashlight
with a red LED light is ideal, or you can cover the front of a
regular incandescent flashlight with red cellophane or paper.
Beware, too, that nearby porch and streetlights and automo-
bile headlights will spoil your night vision.

Eyepiece Selection

By using eyepieces of varying focal lengths, it is possible to
attain many magnifications with the Atlas 8 EQ. The telescope
comes with two high-quality Sirius Plössl eyepieces: a 25mm,
which gives a magnification of 40x, and a 10mm, which gives
a magnification of 100x. Other eyepieces can be used to
achieve higher or lower powers. It is quite common for an
observer to own five or more eyepieces to access a wide
range of magnifications. This allows the observer to choose
the best eyepiece to use depending on the object being
viewed. At least to begin with, the two supplied eyepieces will
suffice nicely.

Whatever you choose to view, always start by inserting your
lowest power (longest focal length) eyepiece to locate and
center the object. Low magnification yields a wide field of
view, which shows a larger area of sky in the eyepiece. This
makes acquiring and centering an object much easier. If you
try to find and center objects with high power (narrow field of
view), it’s like trying to find a needle in a haystack!

Once you’ve centered the object in the eyepiece, you can
switch to higher magnification (shorter focal length eyepiece),
if you wish. This is especially recommended for small and
bright objects, like planets and double stars. The Moon also
takes higher magnifications well.

Deep-sky objects, however, typically look better at medium or
low magnifications. This is because many of them are quite
faint, yet have some extent (apparent width). Deep-sky

objects will often disappear at higher magnifications, since
greater magnification inherently yields dimmer images. This is
not the case for all deep-sky objects, however. Many galaxies
are quite small, yet are somewhat bright, so higher power may
show more detail.

The best rule of thumb with eyepiece selection is to start with
a low power, wide field, and then work your way up in magnifi-
cation. If the object looks better, try an even higher magnifica-
tion. If the object looks worse, then back off the magnification
a little by using a lower power eyepiece.

What to Expect

So what will you see with your telescope? You should be able
to see bands on Jupiter, the rings of Saturn, craters on the
moon, the waxing and waning of Venus, and hundreds of deep
sky objects. Do not expect to see as much color as you in
NASA photos, since those are taken with long-exposure cam-
eras and have “false color” added. Our eyes are not sensitive
enough to see color in deep-sky objects except in a few of the
brightest ones.

Remember that you are seeing these objects using your own
telescope with your own eyes! The object you see in your eye-
piece is in real-time, and not some conveniently provided
image from an expensive space probe. Each session with
your telescope will be a learning experience. Each time you
work with your telescope it will get easier to use, and stellar
objects will become easier to find. Take it from us, there is big
difference between looking at a well-made full-color NASA
image of a deep-sky object in a lit room during the daytime,
and seeing that same object in your telescope at night. One
can merely be a pretty image someone gave to you. The other
is an experience you will never forget!

A. The Moon

With is rocky and cratered surface, the moon is one of the
most interesting and easy subjects for your scope. The best
time to view it is during its partial phases when shadows fall
on the craters and canyon walls to give its features definition.
While the full moon may look like a tempting target, it is actu-
ally the worst time for viewing! The light of a full moon is too
bright and lacks any decent surface definition.

Use an optional Moon filter to dim the Moon when it is very
bright. It simply threads onto the bottom of the eyepiece from
the focuser (you must first remove the eyepiece from the
focuser to attach the filter). You’ll find the Moon filter improves
viewing comfort, and helps bring out the subtle features if the
lunar surface.

B. The Sun

You can change your nighttime telescope into a daytime Sun
viewer by installing an optional full-aperture solar filter over
the front opening of a Atlas 8 EQ. The primary attraction is
sunspots, which change shape, appearance, and location
daily. Sunspots are directly related to magnetic activity in the
Sun. Many observers like to make drawings of sunspots to
monitor how the Sun is changing from day to day.

Содержание Atlas 8 EQ 9873

Страница 1: ...03 Providing Exceptional Consumer Optical Products Since 1975 Customer Support 800 676 1343 E mail support telescope com Corporate Offices 831 763 7000 P O Box 1815 Santa Cruz CA 95061 Orion Atlas 8 EQ 9873 Equatorial Reflector Telescope ...

Страница 2: ...haft lock lever Counterweight shaft Counterweights Counterweight lock knobs Toe Saver Tripod leg Leg lock lever Finder scope Finder scope bracket Eyepiece Focus knob Tube rings Right ascension setting circle Right ascension lock lever Mirror cell Latitude scale Latitude adjustment L bolts Center support shaft not shown Hand controller Tripod support tray ...

Страница 3: ...ray Box 2 1 Equatorial mount 1 Hand controller 1 Battery pack 1 Nylon hook and loop adhesive strip Box 3 1 Optical tube 2 Tube rings 1 Tube ring mounting plate 1 25mm Sirius Plössl eyepiece 1 10mm Sirius Plössl eyepiece 1 9x50 Finder scope 1 Finder scope bracket with O ring 1 Collimation cap 1 Camera adapter 1 Dust cover Congratulations on your purchase of a quality Orion telescope Your new Atlas ...

Страница 4: ...rweight lock knobs are adequately loosened to allow the counterweight shaft to pass through the hole Position the counterweights about halfway up the shaft and tighten the lock knobs Replace the toe saver at the end of the bar The toe saver prevents the counterweights from falling on your foot if the lock knobs happen to come loose 7 Loosen and open the tube rings on the optical tube and remove th...

Страница 5: ...nt is very heavy Alone it weighs 54 lbs With the optical tube and counterweights it weighs almost 100 lbs Keep this in mind when moving the telescope even small distances and use assistance when needed It is best to remove the optical tube and counterweights when moving the mount or extending the tripod legs 4 Balancing the Telescope To ensure smooth movement of the telescope on both axes of the e...

Страница 6: ...serve with your glasses off by just re focusing the telescope the needed amount If you suffer from severe astigmatism however you may find images noticeably sharper with your glasses on Aligning the Finder Scope The Atlas 8 EQ Deluxe comes with a 6x30 achromatic finder scope Figure 3a The number 6 means six times magnifica tion and the 30 indicates a 30mm diameter front lens The finder scope makes...

Страница 7: ...may want to increase the magnifi cation to get a closer view If the object is off center i e it is near the edge of the field of view you will lose it when you increase magnification since the field of view will be narrower with the higher powered eyepiece To change eyepieces first loosen the securing thumbscrew on the focuser s 1 25 adapter Then carefully lift the eyepiece out of the holder Do no...

Страница 8: ...tments to the latitude of the mount nor should you move the tripod Doing so will undo the polar align ment The telescope should be moved only about its R A and Dec axes Using the Polar Axis Finder Scope The Atlas EQ mount comes with a polar axis finder scope Figure 9 housed inside the right ascension axis of the mount When properly aligned and used it makes accurate polar alignment quick and easy ...

Страница 9: ...e tiny circle marked Polaris on the finder s reticle You must first loosen the knob under neath the equatorial mount on the center support shaft to use the azimuth adjustment knobs Once Polaris is proper ly positioned within the reticle you are precisely polar aligned Retighten the knob underneath the mount If you do not have a clear view of Polaris from your observing site you will not be able to...

Страница 10: ...tches one for the R A axis and one for the Dec axis When these switches are flipped to the REV setting the function of the pushbuttons on the hand controller will be reversed The reversal switches allow you to orient the push buttons to the direction of the apparent movement of a guide star in a guide scope for astrophotography Understanding the Setting Circles The setting circles on an equatorial...

Страница 11: ...ience some confusion about how to point the telescope overhead or in other directions In Figure 1 the telescope is pointed north as it would be during polar alignment The counterweight shaft is oriented down ward But it will not look like that when the telescope is point ed in other directions Let s say you want to view an object that is directly overhead at the zenith How do you do it DO NOT make...

Страница 12: ...ersely affects the optical performance of the tele scope or the image quality That might seem counter intuitive but its true Aligning the Secondary Mirror With the collimation cap in place look through the hole in the cap at the secondary diagonal mirror Ignore the reflections for the time being The secondary mirror itself should be cen tered in the focuser drawtube in the direction parallel to th...

Страница 13: ...ck the primary mirror in place a few turns each Figure 17 Use a screwdriv er in the slots if necessary Now try tightening or loosening one of the larger collimation thumbscrews with your fingers Figure 18 Look into the focuser and see if the secondary mirror reflection has moved closer to the center of the primary You can tell this easily with the collimation cap and mirror center mark by simply w...

Страница 14: ...nt of distortion causing atmosphere you are looking through A good way to judge if the seeing is good or not is to look at bright stars about 40 above the horizon If the stars appear to twinkle the atmosphere is significantly distorting the incom ing light and views at high magnifications will not appear sharp If the stars appear steady and do not twinkle seeing conditions are probably good and hi...

Страница 15: ... The Moon also takes higher magnifications well Deep sky objects however typically look better at medium or low magnifications This is because many of them are quite faint yet have some extent apparent width Deep sky objects will often disappear at higher magnifications since greater magnification inherently yields dimmer images This is not the case for all deep sky objects however Many galaxies a...

Страница 16: ...telescopes cannot magnify stars to appear as more than a point of light You can however enjoy the different colors of the stars and locate many pretty double and multiple stars The famous Double Double in the constellation Lyra and the gorgeous two color double star Albireo in Cygnus are favorites Defocusing a star slightly can help bring out its color Deep Sky Objects Under dark skies you can obs...

Страница 17: ...he focuser drawtube Figure 22a Then screw the camera adapter into the focuser drawtube Figure 22b Now attach the T Ring to your camera and thread it onto the camera adapter Figure 22c Use the camera s viewfinder to frame the picture Use the tele scope s focuser to focus the image You may want to consider using a remote shutter release instead of the shutter release on the camera touching the camer...

Страница 18: ...ill need a lock shutter release cable Set the camera s shutter to the B bulb setting Depress the locking shutter release cable and lock it You are now expos ing your first deep sky object While exposing through the camera lens you will need to monitor the accuracy of the mount s tracking by looking through the illuminated reticle eyepiece in the main telescope If the guide star drifts from its ini...

Страница 19: ... a few minutes or hours if it s a very dirty mirror Wipe the mirror under water with clean cotton balls using extremely light pressure and stroking in straight line across the mirror Use one ball for each wipe across the mirror Then rinse the mirror under a stream of lukewarm water Any particles on the surface can be swabbed gently with a series of cotton balls each used just one time Dry the mirr...

Страница 20: ...Watsonville CA 95076 If the product is not registered proof of purchase such as a copy of the original invoice is required This warranty does not apply if in Orion s judgment the instrument has been abused mishan dled or modified nor does it apply to normal wear and tear This warranty gives you specific legal rights and you may also have other rights which vary from state to state For further war ...

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