Prosch Manufacturing Company, New York              1903-1904


An early introduction for the Diaplane Shutter is found in Camera Craft, Volume VI, No. 1, November, 1902.  It only states the name "Diaplane" without enumerating as to Diaplane I or Diaplane II, citing a 1/300th shutter speed which was higher than the Diaplane I's 1/200th maximum speed and lower than the Diaplane II's 1/600th maximum speed.


A more detailed introduction of Prosch's Diaplane Shutters, no doubt a company-prepared release since its essence appeared in several other publications, was noted in The Photographic Times-Bulletin, Volume XXXV, No. 5, May,1903.  It states the Diaplane was made in two styles:  the Diaplane I for amateurs, and the Diaplane II for professionals and advanced amateurs. The Diaplane I had a range of speed from time and bulb, and slow instantaneous exposures to 1/200th of a second, and ranged in price from $17 for the No. 1 size to $22 for the No. 6.  The Diaplane II had an extremely wide range of speed, up to a maximum of 1/600th of a second.

One article in Camera Craft, Volume VII, No. 5, October,1903, stated the Diaplane II could go as high as 1/800th of a second. It was available in sizes No. 3 and upwards, starting at $25.                    


Also during this period, the Prosch Manufacturing Company moved from 389 Broome Street to new and larger quarters at 145 to 151 West 18th Street, New York City on May 1, 1903. Prosch had been located at the previous address for seventeen years.


The Diaplane's design was covered by at least two known patents.  The shutter's face on this example is stamped "Prosch Mfg. Co., Makers, N.Y." along with the serial number.  The rear of the casing is stamped "Pat'd 4.28.'03" just above the lens. This date refers to Patent No. 726,700 granted to Maximilian Klaiber of Brooklyn, New York, the patent being assigned to the Prosch Manufacturing Company. The object of this patent was "to provide a shutter blade operative mechanism which at each extreme movement may be adjusted and set for the next movement, retaining in the device all the advantages of the well known Prosch shutter." 



                               Source:  U.S. Patent and Trademark Office


The second patent, No. 834,812 also granted to Maximilian Klaiber on October 30, 1906, covered other elements of the shutter's design.  This second patent's drawing more closely resembles the Diaplane I's production version. The patent was assigned to the Prosch Photographic Shutter and Optical Company, New York. This company had been formed just a few months prior, having acquired Prosch Mfg. Company's shutter patents:



                               Source:  U.S. Patent and Trademark Office


Instead of Waterhouse stops or a rotary aperture, both the Diaplane I and Diaplane II were fitted with iris apertures, as were all Prosch Shutters being manufactured by that time.


Throwing in a bit of historical timeline:

Polk's (Trow's) Directory for the Boroughs of Manhattan and the Bronx, New York for March,1902 lists Maximilian Klaiber as president of the Prosch Manufacturing Company and Charles Klaiber as secretary, with a capital of $5,000 and Directors: Maximilian, Robert and Charles Klaiber, with an address of 389 Broome.

The New York Times for April 8, 1906 lists the Prosch Photographic Shutter Optical Company, Brooklyn; capital $25,000. Directors Robert Klaiber, Maximilian Klaiber, Howard Pendleton, Jr., New York.

Camera Craft, July, 1906  announced that "The Prosch Photo, Shutter & Optical Company has recently been incorporated, have purchased all the patents and good will of the Prosch Manufacturing Company, and will have opened offices at 1133 Broadway, with factory at 466 Seventeenth Street, Brooklyn, N.Y. Mr. Tatnall, formerly of the Prosch Manufacturing Company, is President and Maximilian Klaiber, who has been connected with the Prosch Manufacturing Company in the shutter department since 1886, is Treasurer and General Manager. The Prosch Manufacturing Company continues in the flash lamp and powder business as heretofore. Yours truly, Prosch Photo, Shutter & Optical Co., J.L. Tatnall, President."


The Diaplane I's most distinguishing feature, and its hallmark among Prosch's shutters, is its oxidized copper finish. I note this with some caution, as I know of no other Diaplane I examples to compare it with. It's also possible this finish could have appeared on previous Prosch models for which no examples have been found. Distinctive and beautiful, oxidized copper finishes can also be found on the Photake Camera of 1896 and some of Eastman's Home Portrait Cameras from 1911 to 1916.  It's interesting to note that a recently seen example of Prosch's Proschlite Flash Lamp, advertised alongside the Diaplane II in the ad seen below, exhibited an oxidized copper finish.

Prosch's ads for the Diaplane II Shutter, which is also featured on this website, appear to reflect a darker finish as well.  Yet, the Diaplane II's finish, as seen on the example featured on this website, is more typical of the brighter brass finishes seen on the majority of Prosch's earlier Duplex and Triplex Shutters.


Both the Diaplane I and Diaplane II disappear by 1905. Although advertised in 1903 and 1904, production probably lasted for a year and a half at best. I was extremely fortunate to have acquired both of these models, and they are the only examples I've ever encountered in the past thirty years.





                  Ad from Anthony & Scovill's The American Annual of Photography and Photographic Times Almanac,1904

                  Image courtesy of HathiTrust and The Getty Research Institute