Prosch Manufacturing Co. (New York, NY)
Duplex Shutter - c. 1885-c.1890s
Scovill Mfg. Co. catalog,
1886, p.
87
Scovill Mfg. Co. catalog,
1886, p.
87 The Prosch Duplex Shutter may
occur as any of three variations, depending on where the shutter's main
components have been placed. Those components are: 1) the lever
that cocks or sets the shutter, 2) the spring that varies the exposure -
the more spring tension, the faster the blades move and the shorter is
the exposure, and 3) the pneumatic piston that controls how fast the
exposure is by expelling the air in the piston through an orifice. Prosch Duplex Shutter
Variation 1: lever is on the top
of the back side, the spring is on the top of the front side, the
pneumatic piston is on the right of the front side. This
configuration and shutter appearance is exactly what is shown in
Prosch's patent drawings (see below), so is assumed to be the first type
made and the oldest variation. I suppose this shutter
could have been mounted backwards, considering that the setting lever is
on the back, but it does have a protruding part on the upper right side
that can be used to set it. This photo is straight at it.
This shutter is mounted on a 5x8"
Eastman Dry Plate & Film Co. Genesee
View Camera, and appears to be a No. 3 size, 3" wide. A photo of
Variation 1 from the front
left. A photo of the back side of
Variation 1. Note that
the configuration of this side matches exactly the engraving for the
Duplex, including the metal label. This is why this shutter can be
identified as a Duplex, and
also the reason to believe that it was installed backwards.
Another example of Prosch Duplex
Shutter Variation 2. This one appears to be a No 3 (~3" wide),
having an
unmarked rapid rectilinear lens with rotating stops. This example
was mounted on a 6½x8½"
American
Optical Co. Flammang's Revolving Back View Camera Variation 1.
Prosch Duplex Shutter Variation 3:
This is the relatively large No. 4 Duplex - about 4" wide. The
configuration is: the lever is on the top of the front side, the spring
is on the right side of the front side, the
pneumatic piston on the left side of the front side. Prosch
finally was able to fit all three essential parts of the shutter all on
the front, but is this possible just because it is a large size?
This shutter is mounted on an 8x10"
Rochester Ideal Variation 1.5. References: Back to
Shutters
1886lp935p87-1500.jpg)
Prosch Duplex Shutter Variation 2:
This is the relatively small No. 1 or No. 2 size (1⅛" lens diameter;
~2½" plate width - most of the very small sizes are very similar in
width and vary only in lens diameter). The configuration is:
lever is at the top of front side, spring is at the right of front side, pneumatic piston
is on the back side. Its main plate has been stamped with a
large "DUPLEX", which, on this small size, is mostly hidden by the
flange of the lens. This shutter is on a 4x5"
American
Optical Co. St. Louis View Camera Variation 2.
Notes:
The
Prosch Duplex and
Prosch Triplex do not appear to have been advertised together -
once the Triplex was developed, the Duplex was apparently obsolete.
The above example is missing the spring on the right side
that somewhat controls the speed.
Illustrated Catalogue of Amateur Photographic
Equipments & Materials, E. &
H.T. Anthony & Co. (New York, NY),
September 1885,
p. 65
Illustrated Catalogue of Amateur Equipments and Materials, E. &
H.T. Anthony & Co. (New York, NY), September 1886, p. 49
Anthony's Photographic Bulletin, Vol. 17, No. 18, E. & H.T.
Anthony & Co., (New York, NY), September 25, 1886, p. 13
How to Make Photographs and Descriptive Price List,
Scovill Mfg. Co. (New York, NY), distributed by
Andrew J. Smith (Providence, RI),
1886, p. 87
Scovill Manf'g Co. Catalogue Photographic Goods, June, 1887, David
Tucker & Co. (Buffalo, NY), June, 1887, pp.142-143
Photographic Lenses and How to Select Them, James W. Queen & Co.
(Philadelphia, PA), 1887, p. 30
An
Illustrated Catalogue of Photographic Cameras, Lenses and Other
Apparatus and Materials for Photography, W.H. Walmsley & Co.
(Philadelphia, PA), April 1, 1888, p. 55
How to
Make Photographs and Descriptive Price List, Scovill Mfg. Co. (New
York, NY), May 1888, pp. 59-60
How to Make Photographs and Descriptive Price List,
Scovill Mfg. Co., distributed by John Wanamaker
(Philadelphia, PA), June 1888,
pp. 59-60
How to Make
Photographs and Descriptive Price List,
Scovill Mfg. Co. (New York, NY), November 1888, pp. 59-60
The International Annual of Anthony's Photographic Bulletin,
Vol. II, 1889, W. J. Harrison and A. H.
Elliot, eds., E. & H. T. Anthony & Co. (New York, NY), ads p. 62
Illustrated Catalogue of Photographic Equipments
and Materials for Amateurs, E. & H.T. Anthony & Co. (New York, NY),
January 1890, pp.51-52
