The German equatorial mount has long been the favored choice of astronomy buffs
and astrophotographers because of its stability and portability. It is more stable
because the center of gravity is directly over the center of its base, and more
portable because it can be broken down into smaller component parts than a fork-mount
telescope for easy storage and transportation.

For astrophotography, the German equatorial mount offers easier balancing; unlimited
space at the rear of the telescope tube to mount a long camera equipment train that
can't bump into the drive base, as is the case with many fork-mounted scopes; and
whole sky access that many fork-mounted scopes can't achieve.

The Celestron CGE PRO - a Sky & Telescope
Hot Product for 2010 - is a newly-designed high payload capacity/high
precision go-to German equatorial mount that epitomizes all of these German equatorial
mount virtues. The CGE PRO has a full 90 pound payload capacity. This allows it
to carry Celestron SCT optical tubes up to 14" in aperture, with as much as 45 pounds
of imaging accessories attached, as well as virtually any other optical tube and
accessory payload weighing up to 90 pounds. The mount is capable of operating over
a latitude range of 10º to 65º in both northern and southern hemispheres. The Sky
& Telescope Hot Product citation said the CGE PRO mount offers "unquestionable
value when it comes to Go To performance for astrophotographers and observers."

The mount's heavy duty right ascension and declination shafts are precision-machined
from 1.57" diameter steel tubing with a stout 0.40" wall thickness. Each shaft is
supported by two preloaded 2.68" O.D. tapered roller bearings. There is a four-point
right ascension and declination clutch system for no-slip pointing precision.

The CGE PRO mount head contains 12VDC slewing/tracking motors with integrated optical
encoders on each axis for go-to computer control. Steel worm gears and brass worm
wheels assure long-term reliability and high accuracy performance. Each precision-made
steel worm gear is 0.75" diameter and is preloaded with two 0.87" OD ball bearings
to minimize run-out (a source of periodic error). The precision-made 255 tooth brass
worm wheel is a full 6" in diameter.

The use of low cog DC Servo motors with integrated optical positioning encoders
offers smooth, quiet operation and precision slewing and tracking. The seven slot
motor armatures are skewed to minimize cogging for precise jitter-free low speed
tracking. The declination worm is spring loaded to minimize backlash for smoother
and easier guiding.

Drive accuracy (periodic error) is a very good +/- 9 arc seconds or better. This
can be further improved by training the permanent periodic error correction circuit
built into the mount's computer hand control to reduce the periodic error inherent
in all telescope worm gear drives.

There are nine motor drive speeds: 0.5x and 1x sidereal for guiding; 4x, 8x, 16x,
and 64x for centering; and 0.5°, 2°, and a fast 5.5° per second for slewing. Preset
tracking rates include sidereal, solar, and lunar. Equatorial tracking modes are
available for both northern and southern hemispheres.

The mount requires 2.5 amp 12 VDC power to operate. The maximum 2.5 amp power draw
happens only briefly when accelerating to the high speed slewing mode from a standing
start. Normal power draw with a well-balanced payload is generally considerably
less than half the maximum draw. The mount comes with a car battery cord to operate
from the cigarette lighter plug of your car or from a rechargeable 12VDC battery
pack. The 17 amp hour capacity Celestron Power Tank #4517V is recommended and will
operate the mount all night long without danger of running out of power.

Specially designed power management electronics deliver constant regulated power
to the motor so that it is capable of driving the mount even when your scope not
perfectly balanced. This allows the CGE Pro to have the payload capacity of that
of much larger (and expensive) mounts without sacrificing smooth tracking motion
and pointing accuracy across the entire sky.

To make a casual no-tool polar alignment for visual use quick and easy, there's
a latitude scale with large ergonomically-friendly altitude and azimuth adjustment
knobs. If serious long exposure astrophotography is in your plans, special All-Star
Polar Alignment software allows you to choose any bright alignment star for a software-assisted
alignment of the mount's polar axis, even if you can't see the North Star.

The CGE Pro mount alone comes with one 22 pound counterweight. When the mount is
supplied as part of a complete telescope package, one counterweight comes with the
9¼" CGE 925 PRO; two come with the 11" CGE 1100 PRO, and three come with the 14"
CGE 1400 PRO and CGE 1400 PRO Fastar. The counterweight is locked in place on the
5 pound steel counterweight shaft with a single hand-tighten knob, making it easy
to rebalance your scope in right ascension if you add heavy photographic accessories.
If needed, optional counterweights are available to balance very heavy loads.

For observing or imaging objects near the meridian (the imaginary line passing directly
overhead from North to South), the CGE PRO is designed to track a full 20° past
the meridian for uninterrupted imaging through the most ideal part of the sky.

An autoguider port, PC port, and auxiliary ports are located on the mount's electronic
pier for long exposure astrophotography. The autoguider port can use a six-pin RJ-12
modular jack ST-4 compatible CCD autoguider to automatically control the drive motors
during long exposure astrophotography. An RS-232 communication port on hand control
allows you to control the mount via a personal computer using the supplied NexRemote
telescope control software.

The CGE PRO mount's adjustable height Super HD tripod has 2.75" diameter stainless
steel legs. It adjusts over a 38" to 55" height range. The height adjustment leg
locks are on the inside of the tripod legs to keep them from snagging on clothing
in the dark. The tripod uses a dual leg support for maximum rigidity, with an upper
leg brace to provide an outward preload and a lower leg brace providing inward tension.
The upper leg brace forms a convenient tray that holds eyepieces and accessories
to keep them up out of the dew-soaked grass.

Optical tubes are installed on the CGE PRO mount using a slot on the mount head
that accepts a Celestron CGE-style or Losmandy D-plate dovetail slide bar. This
allows the optical tube to be quickly and precisely balanced fore and aft on the
mount in declination, eliminating the need for an extra counterweight to balance
a camera or other accessories. Setup and takedown times are exceptionally fast,
as a single large hand-tighten knob holds the optical tube in place. A second lock
knob prevents the tube from sliding off the mount should the hand-tighten knob loosen.

The CGE PRO mount weighs a stout 154 pounds. The equatorial head is the heaviest
component, at 75 pounds. The tripod and electronic pier weigh a combined 52 pounds.
The supplied counterweight weighs 22 pounds, while the thread-in counterweight shaft
weighs 5 pounds. With a deadweight lift of 75 pounds to install the equatorial head
on the tripod, it might be prudent to have a second person assist you in assembling
your CGE Pro mount.