Orion StarBlast 4.5 User manual

MEO Central Library
[phone]
and the Library Telescope Program of the
Back Bay Amateur Astronomers
WARNING: Never look directly at the Sun through this telescope or its finder
scope — even for an instant — as 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.
Orion Star last 4.5" Telescope
Orion Star last 4.5" Telescope
INSTRUCTION MANUAL

Introduction
The BBAA is a 501(c)(3) non-profit scientific and educational organization dedicated to “Bringing
Astronomy to the eople of Hampton Roads.” Founded on December 14, 1978, we are a group of
amateur astronomers drawn together by a common interest in observational astronomy. The BBAA is
an active member society of the Astronomical League [1] and a part of NASA’s Night Sky Network [2].
Visit backbayastro.org [3] to see our calendar of events, club information, newsletters and links to
astronomy-related sites. If you have a question for us please send an e-mail to [email protected]
[4].
lease feel free to bring this telescope and join us at our free monthly Skywatch event at the Northwest
River ark in Chesapeake, VA.
The BBAA provides ongoing support in education and maintenance of this telescope to our library
partners. Our goal is for you to gain a better understanding and appreciation of our universe through
your experience with the telescope. We hope you enjoy using it.
The BBAA would like to thank The New Hampshire Astronomical Society
who originally created this instruction manual.
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Telescope Parts
1) Eyepiece (Zoom 8 to 24 mm)
2) EZ Finder with AA battery box
(See picture below)
3) Telescope tube
4) Focuser (See picture below)
5) Tube Clamp
6) Altitude Clamp
7) Mirror Assembly
8) Support
9) Handle
10) Eyepiece rack (removed)
11) Eyepieces
12) Mount Feet
13) Secondary Mirror Screws
14) Secondary Mirror
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DO NOT TRY TO ADJUST THE ITEMS IN RED

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Focuser
15) Focus wheels
16) Eyepiece securing screws
(Don’t attempt to adjust)
EZ Finder II

Transporting the Te escope
The easiest way to carry the scope is to use the handle (Number 9 in the picture on page 3). If the
scope is too heavy for you to do that you can 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 scope 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.
Care and Maintenance
C eaning the enses or mirrors
Please don’t clean the mirrors. Let the Librarian know if they seem dirty. Eyepieces, however,
can get dirty fairly quickly, particularly when poked with fingers. lease don’t poke them as it’s
very easy to scratch the coatings. However, in case of minor smudges you might try using the
Lens en. First, brush away any dust. Give the cap a quarter twist to replenish the compound on
the cleaning tip inside, then uncover the tip and use it to clean the eyepiece. Be sure to store the
telescope with the dust caps on.
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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 lens with a tissue
or cloth as it has special coatings on it that could be damaged if you do. Please ask people to not
touch the lens… ever.
Telescope Magnification
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 arcminutes (or ½ of a degree) wide, so you could fit about 4 full Moons in the field of
view when using the 8mm setting. Change the Zoom setting until your target fits the eyepiece the
way you like. You will have to adjust the focus.
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Getting Started
lease 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 “ ush-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. 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. The Moon map on this
telescope is “flipped” so it matches what you see in the eyepiece.
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This is important enough to say again:
WARNING: Never look directly at the Sun through this telescope or its finder scope — even for an
instant - as permanent eye damage could result. Do not point the telescope at the Sun, as parts will melt.
Young children should use this telescope only with adult supervision.

Do You Wear Eyeg asses?
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.
Focusing the Te escope
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.
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.
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Operating the EZ Finder
A “finderscope” helps you point the scope. It is similar to a rifle sight. The EZ Finder works by
projecting a tiny red dot onto a screen mounted in the front of the unit, so that when you look
through the screen, the red dot will appear to float in space. Turn the power knob clockwise until
you hear a “click” indicating that power is on. With your eye positioned near the rear of the
telescope, look through the EZ Finder with both eyes open to see the red dot. The intensity of the
dot can be adjusted by turning the power knob. Use the dimmest possible setting that allows you
to see the dot without difficulty. When the EZ Finder is properly aligned with the telescope, an
object that is centered on the EZ Finder’s red dot should also appear in the center of the
telescope’s eyepiece. Checking the alignment of the EZ Finder is easiest during daylight. Aim the
telescope at a distant object, such as the top of a telephone pole or chimney and center it in the
telescope’s eyepiece. Now, turn the EZ Finder on and look through it. The object should appear
near or under the red dot. If not: Without moving the telescope, use the EZ Finder’s left/right
(azimuth) and up/down (altitude) adjustment knobs to position the red dot on the object in the
eyepiece. If the red dot is centered on the object in the eyepiece, you’re done! The finder scope
has a battery pack attached to the telescope. To change batteries, just slide the cover off the pack,
and replace the two AA batteries. At the end of your observing session, be sure to turn the
power knob counterc ockwise unti it c icks off.
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A ign the Finderscope
It is important that the finderscope and the telescope tube are parallel and pointing in the same
direction. 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 Zoom’s 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. If you find that it’s awkward to put your eye up to the eyepiece, you
can rotate the telescope tube by loosening the knob on the tube clamp and moving the telescope
tube until the focuser is in a convenient position. Be sure to tighten it again!
You may find that the telescope tube is either too hard to move or does not stay in place. Use the
altitude adjustment tension knob (it holds the telescope to the upright part of the base) to find the
right level of tension.
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