6
latitude setting should not have to be adjusted again
unless you move to a different viewing location some dis-
tance away.
3. Loosen the Dec. lock lever and rotate the telescope optical
tube until it is parallel with the R.A. axis. The pointer on the
Dec. setting circle should read 90°. Retighten the Dec. lock
lever.
4. Lift and rotate the tripod so the telescope tube (and R.A.
axis) points roughly at Polaris. If you cannot see Polaris
directly from your observing site, consult a compass and
rotate the tripod so the telescope points North.
The equatorial mount is now approximately polar-aligned for
casual observing. More precise polar alignment is required for
astrophotography.
Polar Aligning using the Polar Axis Finder
One of the unique features of your new SkyView Deluxe
mount is the polar axis finder scope. It fits conveniently inside
the equatorial mount, and contains a tiny star map that makes
precise polar alignment quick and easy. To use the polar axis
finder scope, follow these instructions:
1. Approximately polar-align the mount as outlined in the
procedure above.
2. Remove the caps that cover the polar finder (one on the
polar finder’s eyepiece and one on the equatorial mount).
Focus the polar finder by rotating its eyepiece. Now, sight
Polaris in the polar axis finder scope. If you have followed
the approximate polar alignment procedure accurately,
Polaris will probably be within the field of view. If it is not,
move 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.
3. 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 the flashlight while you look through the polar finder.
Note the constellations Cassiopeia and Ursa Major (the Big
Dipper) in the reticle (ignore the constellation Octans, as
this is provided for Southern Hemisphere observers). They
do not appear to scale, but they indicate the general posi-
tions of Cassiopeia and Ursa Major relative to Polaris and
the north celestial pole (which is indicated by the cross at
the center of the reticle). Next, the reticle must be rotated so
the constellations depicted match their current orientation
in the sky when viewed with the naked eye. To do this,
release the R.A. lock lever and rotate the main telescope
about the R.A. axis until the reticle is oriented with the sky.
You may need to reposition the telescope about the declina-
tion axis so the telescope does not bump the mount. Once
the reticle is correctly oriented, use the R.A. lock lever to
secure the main telescope’s position.
4. Now, use the azimuth and latitude adjustment knobs on
the mount to position the star Polaris inside the tiny circle
marked “Polaris” in the polar finder’s reticle. You must first
release the latitude lock lever and loosen the bolt that con-
nects the equatorial head to the tripod (underneath the
equatorial mount). Once Polaris is properly positioned
within the reticle, lock the latitude lock lever and retighten
the bolt that connects the equatorial head to the tripod.
You are now precisely polar-aligned.
If you do not have a clear view of Polaris from your observing
site, then you will not be able to use the polar axis finder
scope to precisely polar-align the telescope.
Note: From this point on in your observing session, you
should not make any further adjustments in the azimuth or
the latitude of the mount, nor should you move the tripod.
Doing so will undo the polar alignment. The telescope
should be moved only about its R.A. and Dec. axes.
tracking Celestial Objects
When you observe a celestial object through the telescope,
you’ll see it drift slowly across the field of view. To keep it in
the field, if your equatorial mount is polar-aligned, just turn the
R.A. slow-motion control. The Dec. slow-motion control is not
needed for tracking. Objects will appear to move faster at
higher magnifications, because the field of view is narrower.
Optional Motor Drives for Automatic tracking
and Astrophotography
An optional DC motor drive (Orion AccuTrack SVD, #7825)
can be mounted on the R.A. axis of the SkyView Deluxe
equatorial mount to provide hands-free tracking. Objects will
then remain stationary in the field of view without any manual
adjustment of the R.A. slow-motion control.
understanding the Setting Circles
The setting circles on an equatorial mount enable you to
locate celestial objects by their “celestial coordinates.” Every
astronomical object resides in a specific location on the
“celestial sphere.” That location is denoted by two numbers:
its right ascension (R.A.) and declination (Dec.). In the same
way, every location on Earth can be described by its longitude
and latitude. R.A. is similar to longitude on Earth, and Dec. is
similar to latitude. The R.A. and Dec. values for celestial
objects can be found in any star atlas or star catalog.
The R.A. setting circle is scaled in hours, from 1 through 24,
with small hash marks in between representing 10-minute
increments (there are 60 minutes in 1 hour of R.A.). The Dec.
setting circle is scaled in degrees (there are 60 arc-minutes in
1 degree of declination).
So, the coordinates for the Orion Nebula listed in a star atlas
will look like this:
R.A. 5h 35.4m Dec. –5° 27'
That’s 5 hours and 35.4 minutes in right ascension, and –5
degrees and 27 arc-minutes in declination (the negative sign
denotes south of the celestial equator).
Before you can use the setting circles to locate objects, the
mount must be precisely polar aligned, and the setting circles
must be calibrated.
