Stony Ridge News
Updated March 24, 2016

March 24, 2016 - A new project start at Stony Ridge Observatory is being delayed due to weather and mechanical issues at the observatory; date TBD.

Stony Ridge Observatory has begun a project with astronomer Dr. Russell Genet from the California Polytechnic State University, San Luis Obispo and students from various colleges. Dr. Genet has recently joined SRO as an Associate member.

Starting with engineering and observing runs extending into the summer, Dr. Genet and his group will use SRO's 30-inch (0.76-m) Carroll telescope to acquire images of closely spaced double stars with the goal of improving upon historical double star data.

Using a special CCD camera, students will take thousands of short exposures at high magnification of many target star systems per night. The data will be further processed by computers running software that will combine the best (sharpest) images to produce sub arc-second resolution of the stellar components. The process utilizes an advanced technique used by professional astronomers called "speckle interferometry" which reduces atmospheric disturbances that cause blurred images.

Details of this project can be found on the SRO Projects page.

This photo taken in June 2015 from a drone hovering above the Stony Ridge Observatory graphically shows the extent to which the Station Fire encroached upon the observatory site in 2009. Looking north-west, above the dome is Mt. Mooney. The terrain to the right (east) drops 2000 feet (615 m.) into Devil's Canyon. Photo courtesy Duncan Martin.

August 17, 2015 - Drive Restoration STATUS REPORT

An SRO Telescope Committee team headed up by committee chairman John Rogers with assistance from Rob Johnson, Andy Gero and Ed Johnson, have completed removal of the Harmonic Drive LLC strain wave drive system and re-installation of the original George Carroll-designed chain drive systems for the 30-inch telescope’s declination and right ascension axes. This change was made because of ongoing problems with interface between the strain wave reduction gears and the telescope's equatorial mount and optical tube assembly.

On the RA axis, the original reduction gear was refurbished and re-installed, but it is now powered by a state-of-the-art digital servo motor with an encoder to track RA position. The DEC axis chain drive incorporates a Boston Gear reduction gear, originally part of a drive update installed years ago, but now incorporating a second digital servo motor and DEC axis encoder.

Photo by Ed Johnson













Warning - Poodle Dog Bush

Another outcome of the Station Fire is the overwhelming growth of the poisonous plant known as Poodle Dog Bush. Be warned that any contact with this weed may cause painful rashes similar to exposure to Poison Ivy or Poison Oak.

For more information visit the USFS - Angeles Forest site.



The digital servo motors, encoders, and associated electronics are part of a new computerized Software Bisque Telescope Control System that allows both power slewing of the telescope using a joystick control, and automatic acquisition of celestial bodies using the software package's computerized go-to features and TheSky-X Professional software. This system will also allow tracking of objects moving at other than the sidereal rate, such as asteroids. The Bisque system is currently operative in "beta" state, with fine tuning and calibration along with some mechanical cleanup activity in progress at this time. Eventually as manpower allows, other updates will be incorporated, including synchronization of dome rotation with telescope motion and remote control of the system from the administration building.

In the course of this work, the DEC and RA axis clutches were re-activated, allowing manual slewing of the telescope in both axes by releasing the clutches. This restores the drive systems on this historic telescope to their originally-designed configuration, with the exception of modern digital drive motors, control system, and go-to capability to replace the old DC analog system.

The next major step is removal and re-aluminization of the primary mirror, whose reflective surface has aged considerably over the eight years since it was last re-coated, and was significantly damaged by ash and gasses from the Station Fire several years ago. This process is currently on hold while the various volunteers and organizations involved coordinate schedules and availability. We hope to get the mirror finished by the end of the year. Considering the current appearance of the mirror’s surface, it still produces amazingly good images. . . .









April 2 , 2014 - Due to the disastrous Station Fire which swept over the observatory site almost 5 years ago, there is still risk of dead trees falling across the road during storms and high winds. This is a continuing problem and we thank the US Forest Service for their response to the clearing of downed trees in the area.

During the past several years, SRO has been engaged in major upgrades to the 30-inch (0.76-m) telescope. The original dual-chain drive right ascension and chain declination drives, designed by George A. Carroll
(1902-1987) were replaced with “strain wave” reduction gears, but on the SRO telescope this system proved to have insufficient accuracy for astrophotography.  Work is now under way to restore the original Carroll-designed drive chains with the addition of modern digital motors and electronic controls to provide the required accuracy, flexibility, and repeatability.  “Go-to” capability will be provided by a commercial software suite.  

Also scheduled this year is cleaning, inspection, and re-aluminization of the 30-inch telescope’s mirrors.    Completion of the drive project will bring this historic telescope back to “better than new” condition.

Future Open House events are expected this year. For additional information and to put your name on the Open House invitation list please email Stony Ridge Observatory.


March 1, 2013 - The continuing legacy of the Station Fire (2009) still inhibits full use of Stony Ridge Observatory. The photo (above) shows two more burned pine trees having fallen across the access road to the observatory. The US Forest Service is responsible for their clearing, estimated to be in the next few weeks. Update: As of March 22, the trees have been cleared and the road is open.
June 3 , 2012 - Some notable guests at SRO's June open house were Dennis Di Cicco and Roger Sinnott (above) of Sky & Telescope Magazine with Dave Hadlen of SRO, Peter Abrahams from the Antique Telescope Society, Larry Webster - site manager at Mt. Wilson's CHARA Array, Nick Kanas, Professor of Psychiatry at the University of California, San Francisco (UCSF) and NASA consultant, and reporter Tom Curwen from the Los Angeles Times. Photo Mike Madsen

February 15, 2012 - Cleanup after the Station Fire is continuing at the observatory. Ground shrubbery is growing back, but the Coulter pine trees that shrouded the site with beauty are gone for many years to come. Currently the Carroll telescope status is back to engineering testing of the newly installed harmonic drive system. The 30-inch mirror will soon be removed for re-aluminizing at the Mt. Wilson Observatory. Stony Ridge Observatory will be hosting an open house in June for participants of the re-enactment of historical observations of the transit of Venus being planned at Mt. Wilson Observatory.

October 7 , 2010 - Power returns to Stony Ridge. On this day, Southern California Edison, the US Forest Service and Acorn Tree Service were busy at the site replacing power poles, supervising, cutting and removing the dead and dying trees as a result of last year's deadly Station Fire. More images of the post-fire recovery work at SRO can been seen in this gallery.

September , 2010 - Stony Ridge Observatory was contacted by Frank Santore in Escondido, CA who is currently restoring a 12-inch Cassegrain reflector that was built by SRO cofounder George Carroll. The equatorial mount on that Carroll telescope is essentially identical to the mount on our Terlep/Carroll telescope that was recently donated to SRO by the John Terlep family (see April 21 below). John Terlep was also a cofounder of SRO. Pictures of this telescope are in the Telescope Gallery.

June 5 , 2010 - Belton, Texas - Today a memorial plaque was reinstalled at the site of the original hanger of the Texas Aero Corporation, makers of the "Temple monoplane" in 1927. Stony Ridge cofounder George Carroll was the Vice President and cofounder of that company. He was also responsible for some of the designs incorporated into the aircraft. Several of Carroll's descendants celebrated in the +100-degree Texas heat. The Texas Aero story can be read from the pages of the Temple Daily Telegram.

June 3 , 2010 - Some members of Stony Ridge made a site inspection today. Recent road work on the dirt road has been done, perhaps by the Southern Calif. Edison Company or the USFS in order for their crews to reach the observatory. New power lines and transformers are visible on poles in the area. On a sad note, our members reported that ALL trees in the area of the observatory appear to be dead. The USFS has begun removing some of the dead trees. USFS personnel have indicated that the lower sections of Angeles Crest Highway, between La Cañada and Red Box, may remain closed until the end of 2011.

May 26 , 2010 - The USFS has announced the opening of a number of areas within the Station Fire Recovery Area. Locations now accessible include Chilao Flats, Newcomb's Ranch and Horse Flats. While the Charlton Flats area is not specifically mentioned, the area is within a few miles from Chilao. Angeles Crest Highway, from La Cañada to Red Box is still closed. Access to Charlton/Chilao can be made via Big Tujunga Canyon Road to Shortcut Saddle. Power and telephone installations are still out at the observatory.

April 22, 2010 - A spokesperson for Southern California Edison has communicated with SRO to say that power restoration in the Stony Ridge area is progressing and that power should be restored to the Observatory by the end of July, 2010.

April 21, 2010 - Stony Ridge Observatory has received a generous donation of a 12.5-inch Cassegrain reflector (image right) from the family of one of the Founding members of SRO, John Terlep. The telescope had been in storage in Pueblo, Colorado for the past several years. John Terlep built the telescope in 1976 under the label of "Terlep Enterprises." A brochure from Rene Corporation of Van Nuys, CA shows the telescope (with its builder) as an example of their manufacturing of high-precision optical instruments. The equatorial mount to which the telescope is attached was built by George Carroll. This mount is the same as one that was used at UCLA for several decades with its 10-inch Wright-Schmidt camera, now retired. That mount is now owned by Kenneth Launie, President of the Antique Telescope Society.
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