The Brandon Refractor
(A history of the Brandon Refractor and the Fox Astronomical Observatory)
(Gary Bloom ? May 2000)
In the late 1960s, Dr. Joseph Dennison Fox, Professor of Astronomy and History, completed his tenure at the University of Puerto Rico and with his wife Sylvia retired to North Miami near Miami Gardens Drive and US-1. He brought with him an optical tube assembly for a 6-inch f/15 refractor. This telescope, in its updated and restored state, still resides in the Fox Observatory on the grounds of Markham Park.
The lens and original tube assembly were built by Chester Brandon, renowned as a designer of eyepieces and objective lenses. Chester Brandon founded Brandon Instruments in the late 1940s in Guaynabo, Puerto Rico, ten miles north of San Juan. After moving to the mainland for work (Maryland/General Precision) in 1959, Brandon sold his tooling and blueprints to VERNONscope and Company in 1963. (VERNONscope, of Candor New York, a telescope and accessory outlet, was founded several years before, in 1958.) The Brandon ocular was designed in 1949, and is still considered one of the better planetary eyepiece designs available. As of August 1996, Chester Brandon was in his 90th year, and living in Wisconsin with his daughter (1904-1998).
The 6-inch objective and the original tube assembly were completed in 1949 or 1950. The lens was ground from special blanks made by Dow-Corning. The uniqueness of the glass and the increased air space and thickness qualified the lens for a new patent. In the late 1950s, Brandon decided to move to the mainland to conduct business, and wanted to find a home for his creation. Brandon was a neighbor and friend of the Fox’s in the San Juan area, and during a visit to the Fox home, talk of what was to happen to this unique instrument came up.
On the evening in question, Dr. Fox showed an interest in acquiring the big refractor. Brandon said there had been many offers, but he had not decided what to do. He wanted the refractor to be available for use by the largest possible number of people. He asked what Dr. Fox would do if he had possession of it. Dr. Fox, being a teacher and consistent with his interest in youth, said the scope would be mounted on the roof for the young people in the area to use. That was apparently what Brandon wanted to hear. The scope changed hands that night for a small sum of money and two sets of Melmac dinnerware. The exact date of the exchange is unknown, but it was sometime in 1958 or early 1959.
Once in his possession Dr. Fox attached the tube assembly with an asbestos covering of his own making (i.e., a heat shield) to an improvised equatorial mount made from part of a landing gear off a World War-II, P-38 fighter. Then, as promised, and using a diving tank as a pier, the telescope was mounted on the roof of the Fox family home where it remained until Dr. Fox retired and moved to South Florida.
In 1965, the South Florida Amateur Astronomers Association Inc., was formed. In 1970, Dr. Fox joined, and in June of 1973, he donated the Brandon refractor to the club. The refractor was to be housed in a yet-to-be-built observatory, located west of Fort Lauderdale. The new observatory would be named for Dr. Fox in recognition of his generosity and leadership. (In the 1970s, the second Thursday of each month was reserved for programs by Dr. Fox. On either the 14th or the 21st of June 1973 at a meeting set aside for one of his talks, Dr. Fox donated the Brandon refractor to the club and to the observatory project. It lacked much of the finish and sophistication it bears today, but it was a start.
By July of 1974, it had been tentatively decided to name the observatory for Dr. Fox. Initial plans for the grounds, building and roof were drawn up 7-13-74. The County okayed the final architectural drawings on November 10, 1975, and the building permit was issued on Thursday, November 13. The observatory was officially named for Dr. Fox a week later, on the 20th.
It took a long time to raise the funds to complete the project, but the pier was poured and work on the refractor was completed in the late months of 1976 through mid February of 1977. The height of the pier was calculated by club member John Martin. With a flat roff-off roof, the measurement had to be exact! The telescope had to fit under the movable part of the roof when it was in the closed position, but the pier still needed be of sufficient height to allow viewing near the horizon. To accomplish both feats, the declination axis would have to be turned to the horizontal position, when the roof was closed. From the time the Fox family moved to Miami, in the late 1960s, until it was permanently installed in the observatory, in 1977, the Brandon Refractor was stored in the Joe and Sylvia Fox’s spare bedroom.)
On Sunday, March 20th, 1977, at 4:30 p.m. (one year behind schedule) the Fox Astronomical Observatory was dedicated. The Brandon refractor with its P-38 mount and asbestos covered aluminum tube was in its present position. (Those who were there will remember seeing Jack Horkheimer–“The Starhustler.”)
In 1978 a vintage 1923, Zeiss mount became available for the 6-inch Brandon refractor through Art Smith of the Miami Space Transit Planetarium. When the new mount was installed, the P-38 mount was stored on the non-movable part of the roof. It remained there, in the open and without cover, until it was finally and unfortunately lost sometime in the 1980s. Two brass counterweight assemblies for the optical tube and a Zeiss rack-and-pinion focuser came with the new mount. The focuser and counterweights were installed with the upgrade, and the asbestos covering Dr. Fox put on the tube in 1958 or 1959, was removed at that time.
Between August of 1993 and July 1995, the Brandon refractor was restored by Tom Peters, a club member and restorations expert. The club voted to put the job of refurbishing the entire instrument, including the Zeiss equatorial mount, in Tom’s skillful hands on August 5, 1993. Everything was dismantled, and the objective was sent to D & G Optical to be refinished. After completion of the task, Barry Greiner, of D & G, mounted the objective in a new aluminum tube, with light baffles. The surface tested at better than 1/20 wave measured at the surface.
When the lens and the new tube returned home, and everything needed to complete the job was in hand. Tom refurbished the mechanical parts, fabricated a new finder and completed reassembly of the various components. Machining or replacement of several pieces within the mount was necessary, and the new finder was born from Tom’s inventory of spare parts. As part of the project, Tom mounted the two Zeiss counterweight assemblies that he had removed from the old tube on the new tube. With the assistance of observatory director Herb Knapp, Tom returned the completed instrument to its pier on July 2, 1995–on July 6, it was fully operational.
(An anecdote: On Saturday night, 11-9-96, a group of us were at the observatory, when another club member, Nick Lawrus, showed up with a few of his favorite eyepieces. Of particular note was a 40 mm K?, with a 60 degree apparent field of view and 95% light transmission. In the 6-inch refractor, this eyepiece, and its 2-inch format, yields 57X and 1.1 degrees of sky. This combination of telescope and eyepiece made it possible to, with averted vision, just barely make out M 110/NGC 205, visual magnitude 10.8, when it was nearly overhead.
NGC 205, the third member of the Andromeda trio of galaxies, considered a test for a 4-inch refractor under dark sky conditions, is difficult given the hazy skies near the city and at the park. While this faint, structureless, 10′ by 5′ oval could be seen in the 6-inch refractor, neither of the other (at that time) observatory telescopes, a 13-inch Dobson and a C14 “could bring it up from the murk.” The turbulence and skyglow, though not significant, were too great an affront to the larger instruments. Of course, under better seeing conditions, the Dobson and the C14 will reveal much fainter objects than the refractor.)
Chester Brandon’s one-of-a-kind telescope has earned a reputation as being both a semi-apochromat and a flat-field refractor. The Brandon refractor with its inherent advantage in imagery, contrast and definition is one of the most remarkable instruments of its size and kind currently in operation. With achromats, the characteristic color shift makes the interpretation of color less accurate, but it may also have a desirable affect on contrast. Whatever the exact reason, the attributes of an f/15 achromat can be starkly beneficial on some objects – especially on Jupiter – and the Brandon refractor seems remarkable in this regard. It may be that the master lens maker designed his refractor with Jupiter in mind: The Great Red Spot appears almost ruby red at its core and is engulfed by luminous aquamarine gas clouds. The surrounding multicolored bands of hydrogen, ammonia and methane stand out in almost three-dimensional relief.
Since the opening of the observatory in 1977, more than 100,000 visitors have observed the heavens through Chester Brandon’s refractor–his intentions and Dr Fox’s dreams were realized! The Brandon refractor is currently on display at the Fox Astronomical Observatory in Markham Park, 12 miles west of Fort Lauderdale on SR-84, and it is available for public viewing every Saturday evening. Organized groups interested in visiting the observatory on these or other dates are asked to contact the observatory director in advance at (954) 384-0442.