Care and maintenance, Specifications, Appendix a: aligning the mirrors – Orion STARBLAST 9814 User Manual

Page 9

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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.

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 gorgeous two-color double star Albireo in Cygnus is a
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, 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. Our eyes are not sensitive enough to see color in
deep-sky objects except in a few of the brightest ones. 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.

To find deep sky objects in the sky, it is best to consult a star
chart or Planisphere. These guides will help you locate the
brightest and best deep-sky objects for viewing with your
StarBlast .

You can also try low-power scanning of the Milky Way. Use the
17mm eyepiece and just cruise through the “star clouds” of
our galaxy. You’ll be amazed at the rich fields of stars and
objects you’ll see! The Milky Way is best observed on summer
and winter evenings.

Care and Maintenance

If you give your telescope reasonable care, it will last a life-
time. Store it in a clean, dry, dust-free place, safe from rapid
temperature changes and humidity. Do not store the telescope
outdoors, although storage in a garage or shed is OK. Small
components like eyepiece and other accessories should be
kept in a protective box or storage case. Keep the dust caps
on the front of the scope and on the focuser when it is not in
use.

The telescope requires very little mechanical maintenance.
The optical tube is made of steel and has a smooth painted
finish that is fairly scratch resistant. If a scratch does appear
on the tube, it will not harm the telescope. Smudges on the
tube can be wiped off with e soft cloth and a household clean-
er such as Windex or Formula 409.

Refer to Appendix B for detailed instructions on how to clean
the optics of the StarBlast.

Specifications

Primary mirror: Parabolic, center marked

Primary mirror diameter: 113mm

Secondary mirror minor axis: 34.3mm

Mirror coatings: Aluminum with Si

O

2

overcoat

Focal length: 450mm

Focal ratio: f/4.0

Focuser: Rack-and-pinion, accepts 1.25" eyepieces

Eyepieces: 17mm and 6mm Explorer II, 1.25"

Magnification: 26x (with 17mm), 75x (with 6mm)

Finder: EZ Finder II reflex sight

Mount: Altazimuth, wood base, eyepiece rack, integral carry handle

Weight: 13 lbs.

Tube Length: 18"

Tube Outer Diameter: 5.5"

Appendix A: Aligning the
Mirrors

Your telescope’s optics were aligned at the factory, and should
not need much adjustment unless the telescope is handled
roughly. Accurate mirror alignment is important to ensure the
peak performance of your telescope, so it should be checked
regularly. Collimating (aligning the mirrors) is relatively easy to
do and can be done in daylight.

To check collimation (mirror alignment), remove the eyepiece
and look down the focuser (4) . You should see the secondary
mirror (16) centered in the drawtube, as well as the reflection
of the primary mirror (15) centered in the secondary mirror,
and the reflection of the secondary mirror (and your eye) cen-
tered in the reflection of the primary mirror, as in Figure 10a. If
anything is off-center, as in Figure 10b, proceed with the fol-
lowing collimation procedure.

The Collimation Cap and Mirror Center Mark

Your StarBlast comes with a collimation cap (17). This is a
simple cap that fits on the focuser like a dust cap, but has a
hole in the center and a silver bottom. This helps center your
eye so that collimating is easy to perform. Figures 10b, c, d
and e assume you have the collimation cap in place.

In addition to the collimation cap, the primary mirror is marked
with a ring with the hole exactly at the center of the primary
mirror. This is of great help in collimating the primary mirror
since you can center the dot of the collimation cap in the mid-
dle of the ring.

Note: The center ring sticker need not ever be removed
from the primary mirror. Because it lies directly in the
shadow of the secondary mirror, its presence in no way
adversely affects the optical performance of the tele-
scope or the image quality.

That might seem

counterintuitive, but it’s true!

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