Orion StarBlast 4.5 User manual

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Syosset Public Library
Orion StarBlast 4.5" Telescope
INSTRUCTION
MANUAL
Syosset Public Library
225 South Oyster Bay Road
Syosset, NY 11791
516.921.7161 ● www.syossetlibrary.org

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WARNING: Never look directly at the
Sun through the telescope or its finder
scope —even for an instant —or
permanent eye damage could result. Do
not point the telescope at the Sun, as
parts will melt!
Children should use this telescope
ONLY with adult supervision.

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Telescope Parts
1) Eyepiece (replaced with zoom eyepiece
8 to 24 mm –glued in)
2) EZ Finder Scope (remember to turn off
when not in use)
3) Telescope tube
4) Focuser
5) Tube Clamp
6) Altitude Clamp (please do not turn this)
7) Mirror Assembly (please do not turn
these screws)
8) Support
9) Handle
10) Eyepiece rack (removed)
11) Eyepiece (replaced by zoom eyepiece)
12) Feet
Focuser Details
13) Focus wheels
14) Eyepiece securing screws (glued in
9place please do not try to turn)

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Transporting the Telescope
The easiest way to carry the telescope is to place your forearm under the telescope
tube when it is in a level position, and lift, holding the upright support against your
side.
When in a car, simply place the telescope on a seat and use a seatbelt to secure it.
The lap belt goes across the base, and the chest belt should cross the tube.

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Care and Maintenance
Regarding cleaning the lenses or mirrors: Don’t. Let the Librarian know if
they seem dirty. Please do not touch the surface of the mirrors (inside the tube) or
the eyepiece lens. Just touching these items will cause damage.
Aligning the Mirrors: Again, please don’t. If it seems that the telescope is in
need of adjustment, please tell the Librarian.
Fog on the mirrors and eyepieces: One of the odd things that happens when
star gazing is that dew forms on pretty much everything (and everyone). The big
mirror is tucked safely down at the bottom of the telescope, and so it does not get
much dew on it. Eyepieces, however, often have dew form on them, making them
useless until they warm up and dry out. If the eyepiece fogs up, wrap your hands
around it for a few moments. As it warms up, the fog should disappear. Please
don’t wipe the eyepiece lens with a tissue or cloth as it has special coatings on it
that could be damaged if you do. Please do not touch the eyepiece lens… ever.
The Eyepiece chart on the telescope shows what magnification you will have for
each setting of the Zoom Eyepiece. The “True Field” describes the width of the
image in the eyepiece. A full Moon is 30 minutes of a degree (or ½ of a degree)
wide, so you could fit about 4 full Moons in the field of view when using the 24mm
setting. Change the Zoom setting until your target fits the eyepiece the way you
like. You will have to tweak the focus.
Modifications: We have tried to make this telescope very easy to use and hard to
damage or lose parts. Many screws and knobs are glued into place or otherwise
made difficult to turn. Please do not try to tighten or loosen any screws or knobs. As
described in this manual, you can move the focus wheels, you can turn the zoom
eyepiece to change the power of magnification and you can turn on the finder scope
but please do not try to turn any other knobs or screws.
The various covers and caps are tied to the telescope to prevent loss. They should
always be in place when the telescope is not in use. Please do not detach the various
strings.

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Getting Started
Telescope should be placed on a flat, stable surface such as a table or park bench.
Please read the instructions and practice with the telescope inside before you take it
out in the dark. The image will be much better if you let the telescope cool down to
air temperature before you start observing.
This is a “Push-to” telescope. Once you find what you are looking for, you can
either watch the object move through your “field of view” (what you see through
the eyepiece) and then reposition the telescope or keep pushing the scope to hold
the object in the center of the eyepiece. Objects appear to move across the field of
view faster at higher magnifications. This is because the field of view becomes
narrower. Why do objects move across your field of view? Because the Earth
rotates……
Like many reflector telescopes, the image in the eyepiece is upside-down.
When looking at star charts you will have to keep this in mind.
Do You Wear Eyeglasses? If so, you will probably be able to observe with
your glasses off by just refocusing the telescope to your unaided vision. If your
eyes are astigmatic, images will probably appear best with glasses on. This is
because a telescope’s focuser can accommodate for nearsightedness or
farsightedness, but not astigmatism. You can also observe with your eyeglasses on.

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This is important enough to say again:
WARNING: Never look directly at the Sun through the telescope or its finder
scope —even for an instant - as permanent eye damage could result. This is one
of the few really bad things you can do to yourself with this telescope. Young
children should use this telescope ONLY with adult supervision.
NEVER POINT THIS TELESCOPE AT THE SUN
Focusing the Telescope: Try out the telescope during the day when you can see
what you’re doing. Remove the dust caps from the eyepiece and telescope tube.
Remember to replace them when done.
The “power” of a given telescope depends upon the eyepiece you use. This scope
has a Zoom eyepiece. Always start by using the telescopes’ lowest-power (turn the
body of the Zoom so the pointer is at “24”) to locate and center an object. Low
magnification shows a larger area of sky in the eyepiece, making finding and
centering an object much easier.
With the eyepiece adjusted for low power (24 mm), aim the telescope in the general
direction of an object at least 1/4-mile away. Slowly rotate the focus wheels until
the object comes into sharp focus. Go a little bit beyond sharp focus until the image
starts to blur again, then reverse the rotation of the knob, just to make sure you’ve
hit the exact focus point. When focusing on stars, bring them to as small a point as
possible.
Many “deep-sky” objects are big, but dim. Low magnification will be better for
them. Once you’ve centered an object in the eyepiece, you can switch to a higher
magnification by twisting the zooms’barrel towards the “8”. This is recommended
for small and bright objects, like planets and double stars. The Moon also takes
higher magnifications well. You may have to refocus a little after changing power.

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Operating the Finder Scope
The finder scope has a wider field of view than the telescope so that it is easier to
find what you want to see. Turn on the finder scope by turning the knob on the right
side. Remember to turn it off when not in use. Point the telescope towards the
object you wish to observe. Look through the finder scope and center the red dot on
the object you want to observe. It may be difficult at first to use the finder scope but
with a little experience it should become easy.
Once an object is centered in the finder scope it should be centered in the telescope
eyepiece as well. If it is not then the finder scope will need to be adjusted. Inform
the Librarian. Please do not try to adjust the finder scope yourself.
What to Expect
Depending upon what is in the sky, planets will look small, but you might be able to
see cloud bands on Jupiter or the rings of Saturn. Craters on the Moon will be clear
and numerous, the waxing and waning of Venus should be visible, and many bright
deep-sky objects will fill the eyepiece. Don’t expect to see color as you do in
NASA photos as 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 eyes! Each session with the telescope will be a learning experience.
Each time you work with the telescope, it will get easier to use, and stellar objects
will become easier to find.

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Objects to Observe:
The Moon is one of the easiest and most interesting targets to view with the telescope.
Lunar craters, “seas”, and even mountain ranges can all be clearly seen from an
average distance of 238,000 miles away! With its ever-changing phases, you’ll get a
new view of the Moon every night it’s up. Make sure to observe the Moon when it is
well above the horizon to get the sharpest images. The best time to observe is during a
partial phase, that is, when the Moon is not full. During partial phases, shadows are
cast on the surface which reveals more detail, especially right along the border
between the dark and light portions of the disk (called the “terminator”).
If the Moon is too bright, or you want a bit more contrast, remove the small plug from
the dust cover and put the cover back on the telescope. This is called “stepping down”
and reduces the light hitting your eye.
Planets do not stay at “fixed” locations like the stars do. To find them you should
refer to the Sky Calendar (telescope.com), or to charts published monthly in
Astronomy, Sky & Telescope, or other astronomy magazines and web sites. Venus,
Jupiter, and Saturn are the brightest objects in the sky after the Sun and the Moon.
Stars: Even powerful telescopes cannot magnify a star 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. Look at the middle star in the handle of the Big
Dipper, Mizar. It is really two stars very close together. Being able to see the two
stars separate is called “Star Splitting”. The gorgeous two-color double star, Albireo,
in Cygnus, is a favorite. Defocusing a star slightly can help bring out its color.
Deep-sky objects: Under dark skies, you can see lots of fascinating deep-sky objects,
including nebulas, 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; many will look like dim gray smudges. 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.
Star clusters are particularly pretty, usually bright, and easy to see.

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When to go observing:
“Seeing” and Transparency: Atmospheric conditions vary significantly from
night to night. “Seeing” refers to the steadiness of the Earth’s atmosphere at a
given time. In conditions of poor seeing, atmospheric turbulence causes objects
viewed through the telescope to “boil”.
In conditions of good seeing, star twinkling is minimal and images appear steady in
the eyepiece. Seeing is best overhead, worst at the horizon. Good “transparency” is
especially important for observing faint objects. Transparency is judged by the
magnitude of the faintest stars you can see with the unaided eye (Mag.1 is very
bright, 2 is dimmer, and so on… 4th magnitude or lower is desirable).