Stony Ridge Telescope Makers


Below and Right: A 4-inch astrograph made in 1953 by SRO founding member Roy R. Cook is shown here in the optical shop of astronomer and telescope collector, John W. Briggs. This telescope was built in the shops of Carroll Astronomical Instruments under direction of SRO's principal founder George Carroll for George Moyen, another of Stony Ridge's originating founding members.



Below: A 12-inch Cassegrain optical tube assembly built by John Terlep; mount by George Carroll. This instrument was donated to Stony Ridge Observatory by the family of John Terlep.





A very early George Carroll Astrograph made in 1953













Below: A 12-inch Cassegrain built by George Carroll. This telescope is housed in a private observatory in Escondido, CA.



The first large reflector built by George Carroll was this 16.5-inch (0.40 m) Newtonian. George donated this instrument to Westmont College in Santa Barbara, California in 1957. Work on Stony Ridge's 30-inch was begun shortly after the completion of this scope.

Westmont College dedicated this instrument in 1957, and named the observatory building that housed it on campus the Carroll Observatory.

Westmont College suffered major fire damage from the "Tea" wildfire a few years back. The 16.5-inch Carroll mirror was destroyed in this fire.

Today, the surviving 16.5-inch telescope, without a primary mirror, is in retirement at Westmont, but the Carroll Observatory was recently rebuilt and currently houses its own 24-inch Keck Telescope.



(Right and 3 Below) This is the configuration of the 30-inch Stony Ridge Observatory's Newtonian/Cassegrain reflector shortly after its completion in 1963. It was designed by George Carroll and built by the members of Stony Ridge Observatory. A documentary film clip can be viewed on this web site which follows the construction of this telescope and the observatory that houses it.

The seemingly complicated details in the machinery shown in the photos below were designed to enable differential tracking speeds, both in Right Ascension (east-west) and Declination (north-south), to track a comet's motion for example.

It was in this configuration, and using the Cassegrain focus, that the telescope was used to produce high-resolution images of the lunar surface. SRO's Lunar Mapping Project (LMP), that ran from February 1964 to August 1967, produced images of the lunar surface that were sent to the Aeronautical Charts and Information Center (ACIC) in St. Louis (a division of the U.S. Air Force). The ACIC produced high-resolution charts used for selecting candidate landing sites for the United States' Apollo manned lunar landing missions. The images from this telescope were used in the production of at least eight of these charts. (SRO is credited in the Portrayal section on this example - 2.3MB jpg chart of the LAC #44 Cleomedes region of the Moon.)



Above: A very early (1949?) Carroll 4-inch refractor with it's original owner Les Mawhinney, former president of the Los Angeles Astronomical Society (LAAS). Les donated the telescope to the LAAS in 1976. It was relocated to the Society's dark sky site in Lockwood Valley. Photo by Mike O'Neal.

Right: The builder, George Carroll with the LAAS scope at the Riverside Telescope Makers Convention (RTMC) in 1980. This telescope was used and tested by two optics experts, Tom Cave and Thomas Cragg, and judged to be one of the finest used by either, rivaling any Alvan Clark instrument of equal aperture. Lew Chilton, of the LAAS reported that the object glass from this scope was stolen within a year or two after the RTMC photo was taken.



Below: George Carroll (far right) displays one of his solar telescope designs at the Riverside Telescope Makers' Convention (RTMC) in 1969.





















Above: George Carroll, designed and built this spar telescope for solar studies at the University of Tel Aviv in 1969. Other spar telescopes were built and installed over Robinson Hall at the California Institute of Technology, and at the Lockheed Solar Observatory, the Big Bear Solar Observatory, Ottawa River Solar Observatory, and perhaps others.


Right: This Carroll 5-inch solar spar telescope recently was on display at the public opening (August 20, 2011) of the new Walking Mountains Science Center in Avon, Colorado.

It was designed and built by George Carroll at the Thomas Tool and Die Company, the company owned by Dave Thomas, Sr., another of Stony Ridge Observatory's Founding members. The telescope is equipped with interchangeable field lenses, including one with interchangeable solar occulting disks. This particular instrument was built in 1974 for the Hopkins Observatory at Williams College (Massachusetts) and dedicated to the memory of Charles J. Hardy, Jr., Chairman of ACF Industries and a member of the Williams College class of 1917.

Presently being restored by John W. Briggs, this telescope will travel to the Mt. Wilson Observatory for observations of the transit of Venus in June, 2012.

Photo courtesy of John W. Briggs


Carroll Spar Telescope
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