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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 galax-
ies 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 
magnification. If the object looks better, try an even higher 
magnification. If the object looks worse, then back off the 
magnification a little by using a lower-power eyepiece.

astronomical objects

Now that you are all set up and ready to go, one critical deci-
sion must be made: what to look at?

a. the Moon

With its rocky and cratered surface, the Moon is one of the 
most interesting and easy subjects to view with your scope.  
The  best  time  to  view  it  is  during  its  partial  phases  when 
shadows fall on the craters and canyon walls to give them 
definition. While the full moon may look like a tempting target, 
it is not optimal for viewing. The light is too bright and surface 
definition is low. 
Even at partial phases, the Moon is very bright. Use of an 
optional Moon filter to helps to dim the view. It simply threads 
onto the bottom of the eyepiece. You’ll find the Moon filter 
improves viewing comfort, and helps bring out the subtle fea-
tures of 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 the telescope. 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. 

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 web site, 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 SkyView Pro 100mm ED EQ is capable of 
showing you these planets in detail. Other planets may be vis-

ible but will likely appear starlike. Because planets are quite 
small in apparent size, optional higher power eyepieces are 
recommended, 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. The tilt 

angle of the rings varies over a period of many years; some-
times 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 seeing) is necessary for a 
good view. Look closely and you may see the Cassini divi-
sion, a thin, dark gap in the rings. You should also see one 
or more of Saturn’s moons, which look like faint stars. The 
brightest is the 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 a close approach to Earth 

every two years. Observing Mars is most favorable at these 
times. With good conditions, you may see a salmon-colored 
disk with some distinct dark patches, and you might be able 
to spot a whitish 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 as tiny points of light. Even the largest tele-
scopes cannot magnify stars to appear as anything more than 
pinpoints. 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 gor-
geous two-color double star Albireo in Cygnus are favorites. 
Defocusing a star slightly can help bring out its color.

E. Deep-Sky objects

Under dark skies, you can observe a wealth of fascinating 
deep-sky objects; that is, objects that reside outside of our 
solar  system. These  include  gaseous  nebulas,  open  and 
globular star clusters, and a variety of different types of galax-
ies. For deep-sky observing 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. 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 from these fascinating objects.
Beginners  are  often  surprised  to  discover  that  the  deep-
sky objects they see through the eyepiece of a telescope 
are mostly grayish, not colorful like those you see in long-
exposure photographs. The reason is that our eyes are not 
sensitive to color in faint light. Still, there is something very 

Summary of Contents for SkyView Pro 100mm ED EQ

Page 1: ...ince 1975 Customer Support 800 676 1343 E mail support telescope com Corporate Offices 831 763 7000 89 Hangar Way Watsonville CA 95076 instruction Manual Orion SkyView Pro 100mm ED EQ Equatorial Apochromatic Refractor Telescope 9977 IN 248 REV C 01 09 ...

Page 2: ... Declination lock lever Right ascension lock lever Right ascension slow motion control knob Counterweight shaft Counterweight Counterweight lock knob Toe saver Eyepiece 1 25 Adapter Finder scope Finder scope bracket 2 Star diagonal Focus knob Latitude adjustment L bolts Tripod support tray Tube rings ...

Page 3: ... are small If anything appears to be missing or broken immediate ly call Orion Customer Support 800 676 1343 or email support telescope com for assistance 2 Parts List Qty Description 1 Tripod 1 Equatorial mount 1 Tripod support tray 1 Central support shaft attached to tripod 1 Tube ring mounting plate 2 Tube rings with mounting screws 1 Counterweight shaft 1 Counterweight 2 Slow motion control kn...

Page 4: ...o the shafts Line up the flat surface on the shaft with the corresponding feature on the interior of the knob to connect them properly The knobs can be attached to either end of the shafts use whichever end is most convenient 9 Attach the tube mounting rings to the tube ring mounting plate using the attachment screws that are on the tube rings The screws should go through the holes on the outer en...

Page 5: ...espect to the right ascension R A axis then the declination Dec axis 1 Keeping one hand on the telescope optical tube loosen the R A lock lever Make sure the Dec lock lever is locked for now The telescope should now be able to rotate freely about the right ascension axis Rotate it until the counter weight shaft is parallel to the ground i e horizontal 2 Now loosen the counterweight lock knob and s...

Page 6: ...The finder scope view will be rotated 180 Figure 7 If you have trouble focusing rotate the focus knob so the draw tube is in as far as it will go Now look through the eyepiece while slowly rotating the focus knob in the opposite direction You should soon see the point at which focus is reached Note About the Crayford Focuser The SkyView Pro 100mm ED EQ comes equipped with a Crayford focuser The Cr...

Page 7: ...en you look through the finder scope the images appear somewhat out of focus you will need to refocus the find er scope for your eyes Loosen the focus lock ring located behind the objective lens cell on the body of the finder scope see Figure 3a Back the lock ring off by a few turns for now Refocus the finder scope on a distant object by threading the objective lens cell in or out of the finder sc...

Page 8: ...m an image Most astronomical objects emit a spectrum comprised of many dif ferent wavelengths of light so each wavelength will be bent by a slightly different amount when passing through a lens This results in each color of light reaching precise focus at a slightly different point which will provide unacceptable images The 100mm ED is designed to minimize chromatic aberra tion The objective lens ...

Page 9: ...al observing More precise polar alignment is recommended for astropho tography For this we suggest using the optional polar axis finder scope From this point on in your observing session you should not make any further adjustments 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 Polar A...

Page 10: ... the tripod left to right and adjust the latitude up and down until Polaris is somewhere within the field of view of the polar axis finder scope 5 Shine a red flashlight down the front end of the polar finder to illuminate the reticle within the field of view Make sure the flashlight shines in at an angle so as not to block the polar finder s field of view It may be helpful to have a friend hold t...

Page 11: ...main stationary in the field of view without any manual adjustment of the right ascension slow motion control knob Understanding the Setting Circles The setting circles on an equatorial mount enable you to locate celestial objects by their celestial coordinates Every object resides in a specific location on the celestial sphere That location is denoted by two numbers its right ascension R A and de...

Page 12: ... 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 pointed 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 any adjustment to the latitude adjustment L bolts That will spoil the mount s polar alignment Rem...

Page 13: ...your SkyView Pro 100mm ED EQ to acclimate If the scope has more than a 40 tempera ture change allow an hour or more In the winter storing the telescope outdoors in a shed or garage greatly reduces the amount of time needed for the optics to reach thermal equi librium It also is a good idea to keep the scope covered until the Sun sets so the tube does not heat greatly above the tem perature of the ...

Page 14: ...anets are quite small in apparent size optional higher power eyepieces are recommended 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 Highe...

Page 15: ...r if possible Move the telescope slightly until the telescope is centered on the new star Continue using stars as guideposts in this way until you are at the approximate position of the object you are trying to find Figure 16 Look in the telescope s eyepiece and the object should be somewhere within the field of view If it s not sweep the telescope carefully around the immediate vicinity until the...

Page 16: ... the whole system into the focuser with the camera adapter that comes with the telescope attached to the drawtube and secure firm ly with the thumb screws Aim the telescope at the planet or Moon you wish to shoot The image will be highly magnified so you may need to use the finder scope to center it within the camera s viewfinder Turn the motor drive on Adjust the telescope s focuser so that the i...

Page 17: ...0mm ED EQ requires very little mechan ical maintenance The optical tube is aluminum and has a smooth painted finish that is fairly scratch resistant If a scratch does appear on the tube it will not harm the tele scope Smudges on the tube can be wiped off with a soft cloth and a household surface cleaner Cleaning Lenses Any quality optical lens cleaning tissue and optical lens clean ing fluid speci...

Page 18: ...ngar Way 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 mishandled 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 furt...

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