TIME AND INSTANTANEOUS DIAPHRAGM SHUTTER - MODEL OF 1890

Bausch & Lomb Optical Company, Rochester, New York 1889-1890

This third model in Bausch & Lomb's Diaphragm series is identified by an inverted "V" dual valve arrangement that was intended to provide more uniform movement. Sometime in late 1889, this new configuration was intended to replace the horizontal valve found on the 1889 model. For lack of a formal name, I've designated this shutter as the Time and Instantaneous Shutter - Model of 1890, to place it chronologically and to distinguish it from the other shutters in the series.

This shutter's May 15 '88 patent date is located on the front housing below the lens. Taken from Dr. Rudolf Kingslake's description of the shutter, two adjustable cranks were now fitted to the spring drum, one to control the maximum shutter opening and the other to vary the movement of the air valves. Two pointers attached to the levers controlling these cranks are shown in the diagram above, the speed dial being on the left drawing and the aperture dial on the right drawing. A third radial lever located in the middle of the spring drum permitted time or instantaneous exposures to be made.

Dr. Rudolph Kingslake, preeminent lens expert and historian, was hired as the Chief Lens Designer for Eastman Kodak in 1937. After 32 years, many of which were spent leading Eastman's Optical Department, he retired in 1969. Subsequently working with the George Eastman House as it was known then, he helped in cataloging their technology collection. In an article titled "The Bausch & Lomb Shutters", written for the Western Photographic Collector's Association's journal, The Photographist, Summer, 1981, Dr. Kingslake outlines Bausch & Lomb's earliest shutters, providing a photo of the Model of 1890. The shutters profiled were those from a collection of early shutters given to the George Eastman House by Bausch & Lomb. Highlighted were many that reached production, this "Model of 1890", and several prototypes that were never marketed.

Several factors suggest that the Model of 1890 may have reached production, one being that the example in Dr. Kingslake's article clearly shows a serial number. There is also mention of the shutter in The American Amateur Photographer, Volume II, No. 3 for March,1890, in an article titled "Camera Shutters-No. 2", by F.C. Beach. The article refers to it as “Bausch & Lomb’s Improved Shutter" , with a schematic sketch showing the inverted valves and a statement from Beach noting that "Altogether it is a finely made instrument and generally works well. I have used it for some little time. Have found that the parts made of steel rust some and slightly impede the movement, a point, however, which is not serious." Based upon the sketch, it's assumed that Beach is describing the Model of 1890, and not the Model 1889, a description of which follows it in the same article. Based on the foregoing, one could infer that the shutter had been produced and sold, or that production was eminent and this was a pre-release review by a respected individual in the photographic field. If the latter were true, it infers Bausch & Lomb would have turned over a sole prototype to someone for testing. This seems an unlikely scenario unless Bausch & Lomb had built a few other examples, but who can say for sure.

Another possibility is that the factory could have taken an already serial-numbered casing off the Model 1889's assembly line to produce a prototype that never reached production. Having no serial numbering information to go by, I'm guessing that in Bausch & Lomb's earliest years of manufacturing shutters and having just the one Diaphragm shutter series, the numbers would have continued to build from one model to the next. So it's entirely possible that a prototype could have had a serial number, as any modifications or improvements were incorporated, and production continued. In support of this premise, looking at all the Iris Diaphragm Shutter - Model of 1891 (the Model of 1890's successor) examples in my collection, no serial numbers were found to be lower than what appears to be Serial No. 653 shown in the above photo of the Model of 1890. Further, none of the Iris Diaphragm Shutter - Model of 1891 examples in my collection have a 3-digit serial number, all having a 4 or 5-digit numbers. Also, the Model 1889 examples in the collection all have 3-digit serial numbers, two of which were higher than Serial No. 653.

This all tends to suggest that the Model of 1890 was a prototype, conceived at some point in the Model 1889's production run, which continued forward for a time after the Model of 1890's development was halted. It's also possible that a very limited number of units were built before the design was abandoned, and it all happened before any advertisement occurred.

The example in the George Eastman Museum is the only one I'm aware of, and more research may reveal whether this model ever reached production. Its existence as a possible prototype, is supported by no other known examples to my knowledge and no factory advertisements found so far.

If ever produced, the Time and Instantaneous Shutter - Model of 1890 would be without question the rarest of Bausch & Lomb's Diaphragm shutters, as well as being the rarest Bausch & Lomb shutter.....period.

Excerpt on camera shutters from The American Amateur Photographer 1890

Source: The Bausch & Lomb Shutters, Dr. Rudolph Kingslake, The Photographist, Summer, 1981