Grove Creek Observatory's Telescopes & Equipment:

                      Short Summary:

THE CELESTRON C-14 SCHMIDT CASSEGRAIN:

Celestron Pacific C14 Schmidt Cassegrain Telescope
Aperture: 36cm (14")  Focal Length: 3,910mm  Focal Ratio: f/11
(Pictured with Steven Williams)
A very unique telescope with somewhat of a unique history....

Watch our video about our C14

Viewing through the C14 Telescope:

Light Path through a Schmidt Cassegrain Telescope

Housed in our main motorised 3.2 meter (10 foot) dome, is our massive Celestron C14. This is our main viewing instrument and with a focal length of 3,910mm (154"), this telescope is used for high resolution objects. Being a Schmidt Cassegrain, it provides a higher contrast than even larger Newtonian telescopes. The C14 was built in 1971 and was the second model made by the "Celestron Pacific" telescope company, using the original sturdy "sand-cast" rigid fork. Its 36cm (14") primary mirror is of an exceptional high optical standard - going beyond testing equipment that could measure an accuracy of 1/10 wavelength of light. The C14 can operate visually at f/11 or f/7 and can be configured with huge a variety of combinations for different types of astrophotography and CCD imaging. The C14 is mounted on a home made equatorial wedge, that is made out of 23mm (0.9") thick stainless steel. This is attached to a huge pier, which is driven 6 metres (19.5 ft) into the ground and is totally isolated with no part of the building touching it. The pier is 50cm (20") diameter and constructed with a solid steel core of 18cm (7") diameter, surrounded by concrete, sealed with a large gas pipe on the outside.

The C14 at Grove Creek has its own fame, as many live astronomical events were recorded with special video cameras attached, including live images of the Shoemaker-Levy Comet hitting Jupiter, that were shown throughout the world on Australian and international TV, including CNN, and the BBC, in July 1994. Well over 10,000 people viewed Halley's Comet through this telescope when it was installed at Grove Creek in 1985.

In 1998, extensive upgrades were made to replace the old original Right Ascension AC clock tracking and DC slewing motor (abbrev. "RA" - the east/west movement) and the DC Declination motor (abbrev. "DEC" - the north/south movement) with a home-made Z-80 processor controlled stepping motor control system, designed and built by electronics expert Chris Ralph and astronomer Steven Williams. For the first time on such an old mount, high magnification "auto-guiding" astrophotography and the early days of astronomical CCD imaging was then made possible with this system. Along with the electronic tracking upgrades, a Celestron Astro-Master computerised digital setting circle was also installed, to make finding objects a breeze. An innovation that  was never even dreamed of, when the mount was designed 30 years ago! Previously, tedious sightings had to be read from old mechanical setting circles attached to the mount. Grove Creek was one of the first observatories to purchase a SBIG ST-4 CCD autoguider and stunning film photos were achieved as a result.

Then two disasters struck... In 1999, one of the most severe storms ever seen in the area totally blew the entire 300kgs dome off its rails, driving it into the telescope's mount and destroyed the delicate RA gearing system and mounting hardware for the optical encoders. However, even with such amazing force, the optics of this ruggedly built telescope didn't even loose collimation! Fortunately (and very generously) Celestron, understanding that this particular telescope was of special vintage, re-built the RA gear system at no charge and the dome was modified so such an horrible incident could never happen again. However, to the complete dread of everyone involved with Grove Creek, a violent electrical strike directly hit the C14 in 2002, which not only caused massive damage to most of the electrical devices and appliances throughout the observatory but totally destroyed both the home-made drive controller, Astro-Master and optical encoders!  Parts for the previous home-made drive system were no longer available, so it was replaced with a third-party commercial computerised duel stepping motor drive system.  The Celestron Astro-Master was replaced with a Argo Navis digital setting circle computer, with RS2-232 planetarium control functions from Wildcard Innovations.

As all our telescopes are mostly dedicated CCD imaging instruments and can not be viewed through, we have this telescope available for viewing use in the main dome. In January 2009, a special pier adaptor plate was installed by Brett Soames to enable a LX-200 Wedge base, Paramount ME mount or to put back the original C-14 fork on the main pier. The previous C14 was moved into the middle observatory for robotic use in May 2008. A CCD camera for personal use can be easily installed, operated from a PC in the control room.