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Important Note: Do not look at the Sun with any optical
instrument without a professionally made solar filter, or
permanent eye damage could result. Also, be sure to
cover the finder scope, or better yet, remove it altogether.

C. The Planets

The planets don’t stay put like the stars, so to find them you
should refer to Sky Calendar at our website telescope.com, or
to charts published monthly in Astronomy, Sky & Telescope,
or other astronomy magazines. Venus, Mars, Jupiter, and
Saturn are the brightest objects in the sky after the Sun and
the Moon. Your Atlas 8 EQ is capable of showing you these
planets in some detail. Other planets may be visible but will
likely appear starlike. Because planets are quite small in
apparent size, optional higher power eyepieces are recom-
mended and often needed for detailed observations. Not all
the planets are generally visible at any one time.

JUPITER  The largest planet, Jupiter, is a great subject for
observation. You can see the disk of the giant planet and
watch the ever-changing positions of its four largest moons—
Io, Callisto, Europa, and Ganymede. Higher power eyepieces
should bring out the cloud bands on the planet’s disk.

SATURN The ringed planet is a breathtaking sight when it is
well positioned. The tilt angle of the rings varies over a period
of many years; sometimes they are seen edge-on, while at
other times they are broadside and look like giant “ears” on
each side of Saturn’s disk. A steady atmosphere (good see-
ing) is necessary for a good view. You will probably see a
bright “star” close by, which is Saturn’s brightest moon, Titan.

VENUS At its brightest, Venus is the most luminous object in
the sky, excluding the Sun and the Moon. It is so bright that
sometimes it is visible to the naked eye during full daylight!
Ironically, Venus appears as a thin crescent, not a full disk,
when at its peak brightness. Because it is so close to the Sun,
it never wanders too far from the morning or evening horizon.
No surface markings can be seen on Venus, which is always
shrouded in dense clouds.

MARS The Red Planet makes its closest approach to Earth
every two years. During close approaches you’ll see a red
disk, and may be able to see the polar ice cap. To see surface
detail on Mars, you will need a high power eyepiece and very
steady air!

D. The Stars

Stars will appear like twinkling points of light. Even powerful
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 observe a wealth of fascinating
deep-sky objects, including gaseous nebulas, open and glob-
ular star clusters, and a variety of different types of galaxies.
Most deep-sky objects are very faint, so it is important that

you find an observing site well away from light pollution. Take
plenty of time to let your eyes adjust to the darkness. Do not
expect these subjects to appear like the photographs you see
in books and magazines; most will look like dim gray
smudges. But as you become more experienced and your
observing skills get sharper, you will be able to ferret out more
and more subtle details and structure.

How to Find Deep-sky Objects: Starhopping

Starhopping, as it is called by astronomers, is perhaps the
simplest way to hunt down objects to view in the night sky. It
entails first pointing the telescope at a star close to the object
you wish to observe, and then progressing to other stars clos-
er and closer to the object until it is in the field of view of the
eyepiece. It is a very intuitive technique that has been
employed for hundreds of years by professional and amateur
astronomers alike. Keep in mind, as with any new task, that
starhopping may seem challenging at first, but will become
easier over time and with practice.

To starhop, only a minimal amount of additional equipment is
necessary. A star chart or atlas that shows stars to at least
magnitude 5 is required. Select one that shows the positions
of many deep-sky objects, so you will have a lot of options to
choose from. If you do not know the positions of the constella-
tions in the night sky, you will need to get a planisphere to
identify them.

Start by choosing bright objects to view. The brightness of an
object is measured by its visual magnitude; the brighter an

Figure 21. 

Starhopping is a good way to locate hard-to-find

objects. Refer to a star chart to map a route to the object that uses
bright stars as guideposts. Center the first star you’ve chosen in the
finder scope and telescope eyepiece (1). Now move the scope
carefully in the direction of the next bright star (2), until it is
centered. Repeat (3 and 4). The last hop (5) should place the
desired object in the eyepiece.

Summary of Contents for Atlas 8 EQ 9873

Page 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 ...

Page 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 ...

Page 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 ...

Page 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...

Page 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...

Page 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...

Page 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...

Page 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 ...

Page 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...

Page 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...

Page 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...

Page 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...

Page 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...

Page 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...

Page 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...

Page 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...

Page 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...

Page 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...

Page 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...

Page 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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