Orion 8 EQ - Manual (Page 6)

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5. Using Your Telescope
Focusing the Telescope
With the 25mm eyepiece inserted in the focuser, move the tel-
escope so the front (open) end is pointing in the general
direction of an object at least 1/4-mile away. Now, with your
fingers, slowly rotate one of the focusing knobs until the object
comes into sharp focus. Go a little bit beyond sharp focus until
the image just starts to blur again, then reverse the rotation of
the knob, just to make sure you’ve hit the exact focus point.
NOTE: The image in the telescope will appear rotated
180° (upside down and reversed left-to-right). This is nor-
mal for astronomical scopes .The finder scope view will
also be rotated 180°. (see Figure 6)
If you have trouble focusing, rotate the focusing knob so the
drawtube is in as far as it will go. Now look through the eye-
piece while slowly rotating the focusing knob in the opposite
direction. You should soon see the point at which focus is
reached.
The black nylon thumb screw on the top of the body of the
focuser (see Figure 4) will lock the focuser drawtube in place
once the telescope is properly focused. Before focusing,
remember to first loosen this thumb screw.
Viewing with Eyeglasses
If you wear eyeglasses, you may able to keep them on while
you observe, if the eyepiece has enough “eye relief” to allow
you to see the whole field of view. You can try this by looking
through the eyepiece first with your glasses on, and then with
them off, and see if the glasses restrict the view to only a por-
tion of the full field. If they do, you can easily observe 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 SkyView Pro 8 EQ Deluxe comes with a 6x30 achromatic
finder scope (Figure 3a). The number 6 means six-times magni-
fication and the 30 indicates a 30mm diameter front lens. The
finder scope makes it easier to locate the subject you want to
observe in the telescope, because the finder scope has a much
wider field-of-view.
The SkyView Pro 8 EQ’s finder scope uses a spring-loaded
bracket that makes alignment of the finderscope very easy. As
you turn either of the thumbscrews, the spring in the bracket’s
tensioner moves in and out to keep the finder scope secure in
the bracket.
The finder scope must be aligned accurately with the telescope
for proper use. To align it, first aim the main telescope in the gen-
eral direction of an object at least a 1/4 mile away - the top of a
telephone pole, a chimney, etc. To aim the telescope, loosen the
R.A. and Dec. lock levers and move it until it is pointing at the
desired object. Then sight along the tube to aim the telescope.
Turn the focus knob until the object is properly focused. Make
sure to position the object in the center of the telescope’s eye-
piece by turning the R.A. and Dec. slow-motion control knobs.
Now look in the finder scope. Is the object visible? Ideally it will
be somewhere in the field of view. If not, some coarse adjust-
ment to the finder scope bracket’s alignment thumbscrews will
be needed until the object comes into the finder scope’s field of
view.
With the image in the finder scope’s field of view, you now need
to fine-adjust the alignment thumbscrews to center the object on
the intersection of the crosshairs. Adjust the aim of the finder
scope by turning the thumbscrews, one at a time, until the object
is centered.
The finder scope alignment needs to be checked before every
observing session. This can easily be done at night, before view-
ing through the telescope. Choose any bright star or planet,
center the object in telescope eyepiece, and then adjust the find-
er scope bracket’s alignment thumbscrews until the star or
planet is centered on the finder’s crosshairs.
Focusing the finder scope
If, when you look through the finder scope, the images appear
somewhat out of focus, you will need to refocus the finder
scope for your eyes. Loosen the 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 finderscope body. Precise focusing will
be achieved by focusing the finder scope on a bright star.
Once the image appears sharp, retighten the locking ring
behind the objective lens cell. The finder scope’s focus should
not need to be adjusted again.
Magnification & Eyepieces
Magnification, or power, is determined by the focal length of
the telescope and the focal length of the eyepiece. Therefore,
by using eyepieces of different focal lengths, the resultant
magnification can be varied.
Naked-eye view
View through finder scope and telescope
Figure 6. The view through a standard finder scope and reflector
telescope is rotated 180°. This is true for the SkyView Pro 8 EQ and
its finder scope as well.