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Celestron Ultima 9-1/4 (235mm) Schmidt-Cassegrain Telescope telescope/fork mount assembly is discontinued - optical tube remains available for use with a variety of suitable German Equatorial Mounts

The Celestron Ultima 9-1/4 Schmidt-Cassegrain Telescope introduced in October of 1995 is the first new aperture offered by Celestron since the 1970's. This telescope replaced the "Ultima 8 PEC" telescope and it is a good example of what is possible in a ergonomic SCT geared for astrophotography while also retaining very good observing characteristics.

Celestron Ultima 9-1/4
This telescope incorporates an up-dated Schmidt-Cassegrain design of 9-1/4" (235mm) aperture with a nominal focal length of 2350mm resulting in an f10 system. This increase in aperture over a comparable 8" telescope results in a significant light gathering power 1.34X that of an 8" telescope, and still the telescope remains quite manageable by one person of average stature. This focal length still permits a good close-up photo of the entire full moon onto a standard 35mm film format with no need for optional telecompressor (focal length reducing) lense. And at prime focus magnifications as low as 43X covering 1.17 degree field of view are practical; with an optional telecompressor lens this actual field of view can be increased. The design of these optics offer improved contrast even over traditional f10 Schmidt-Cassegrain telescopes, this is due to the slightly different optical prescription for the primary mirror and secondary mirror system. And as with all Celestron SCT's, these are truly made in the U.S.A.!

A rugged, highly damped fork mount with an adjustable clutched tangent arm Declination manual control, with sand cast drive base makes viewing and astrophotography a delight. It has extra large fork tines with Dec. setting circles, and an extra large polar shaft integrally cast into the base. it includes precision preloaded polar axis ball bearings. The drive base also incorporates a clutched manual control for Right Ascension, with a driven R.A. setting circle.

Some of the Ultima 9-1/4 features (similar to the older Ultima 8 PEC telescope): a totally cordless DC Servo quartz drive system with hand controller. The system electronics incorporate PEC (Periodic Error Correction) with an easy 4 minute recording cycle, highly accurate worm gear drive, four tracking rates including King, sidereal, lunar and solar and a slewing speed of 400% sidereal rate. In a Sky & Telescope review of 8" Schmidt-Cassegrains, it was noted, "the Ultima 8's drive error was the least I have ever seen in a mass-market telescope." Astronomy Magazine said of the drive, "a textbook straight line" and "the PEC is impressive. It worked better than advertised."

The power-efficient Ultima 9-1/4 runs from a 9V alkaline battery. AC or 12V operation of the Ultima 9-1/4 is possible with optional adapters. In addition, it can be used in either the Northern or Southern Hemisphere.

A Sky & Telescope review of the Ultima 8 summarized it nicely saying, "Which telescope would I buy? ... For me the choice was easy. The superb drive and solid mounting of the Ultima (8) are very seductive features for an astrophotographer. A drive that requires no external cords or power supply makes a perfect instrument to take along for casual observing. Coupled with these features are optics rated as the most consistent."

Ergonomic user-friendly operation is the trademark of the Ultima 9-1/4. It was designed with functional use foremost. Convenient carrying handles are provided on the fork tines and the rear cell for ease of handling and transport. The focus knob and all controls are scaled for use even when wearing gloves. And the focuser incorporates a micrometer with a digital display to aid those who wish to employ the system for astrophotography and CCD imaging!

Included is the Celestron "heavy duty" wedge with latitude scale and accessory tray. With the wedge is included the "Wedge Upgrade Kit" that includes: deluxe latitude adjuster for fine control of tilt plate (up-down) motion, azimuth adjuster for fine control of wedge (left to right) motion. The adjustable height, two section periscoping metal field tripod is also furnished as standard equipment.

When this telescope was originally introduced, in order to aid rigidity Celestron was including a set of thier three Vibration Suppression Pads to help dampen any vibrations that might make their way through the system. This was a meaningful improvement to the telescope which has been deleted as a standard accessory with this telescope since January 1998. We suggest our customers who buy this (and some other telescopes) buy the VSP which are remains an available option.

Standard accessories include: 6 x 30mm Finderscope (nearly useless - we suggest most users upgrade this), Prism Star Diagonal 1-1/4", Visual Accessory Back 1-1/4", and a 25mm Modified Achromat Eyepiece 1-1/4" (94x). Weight is 74 lbs.

Celestron Schmidt-Cassegrain Telescopes
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