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.      


Unlike the Prosch Diaplane I featured on this website, the shutter's face is not marked with the maker's name or serial number. There is an oval stamping that appears to be either "NIM Co". or "MIM Co.", possibly a distributor's mark, and the mounting ring is marked "Germany" suggesting it to be non-original.  Also, the rear of the casing is not stamped "Pat'd 4.28.'03", as on the Diaplane I. For more history and patent information covering both the Diaplane I and Diaplane II, see the Prosch Diaplane I featured on this website.

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. As seen below, Prosch's ads for the Diaplane II Shutter reflect a darker finish.  Yet, the Diaplane II's finish, as seen on this example is more typical of the brighter brass finishes seen on the majority of Prosch's 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