In addition to the usual version of the Copal shutters as supplied with virtually all large format lenses in current manufacture Copal makes another version: The Press Shutter. In the standard version the shutter is operated on a "set and release" principle. That is, a finger operation is needed to "cock" (in reality, "wind up") the shutter. Operation is then by cable release or the release lever. The advantage of this design is twofold: First there is speed of operation, the shutter is always ready for exposure and never needs to be cocked. Second, and of great importance especially to architectural photographers is the ability to make multiple exposures without any risk of disturbing the camera setup. This means that you can take a flash picture, move the flash to another place, make another exposure, and repeat this procedure to light up a large area with only one or two flash heads. With the shutter set at 1/125 second ambient light will not add up and very dramatic results can be obtained. In the case of the Press (I don't know the origin of why this term is applied) shutter all the operation is done via the release lever or cable release. Some extra energy is needed since the cable release actually winds up the mechanism of the shutter. Most of the specifications are the same as the ordinary shutters except: Top speeds are slower: fastest speed is 1/125 sec #0 Minimum iris opening is 2 mm on the press, 1.5 mm on regular. #1 Minimum iris opening is 2.5mm on the press, 2 mm on regular. The iris is about 0.75mm farther back in the shutter. The iris diaphragm is a spring loaded affair that is held open when the press focus is operated. All "press" viewing is at full aperture. In order to view thru a selected aperture the shutter must be set to "B" or "T" Not available in #3 size. We routinely install lenses in these,mounted to your lensboard and ready to use. Because of the differences between the shutter versions some attention and experience is needed to ensure proper operation. Iris scales from the standard shutter do not fit the Press shutter. To view a set of drawings of the shutters listed, click below and use scroll bars to see the whole image: Copal Press #0 click once here Copal Press #1 click once here These drawings are from the original instruction sheets. Copal Press Dimensions and Specs COPAL spec. #0 #1 front thread M29.5-0.5 M40-0.75 back thread M29.5-0.5 M36-0.75 overall thickness 20 mm 20 mm front to iris 11.7 mm 11.7 mm mount thread M32.5-0.5 M39-0.75 lensboard hole 34.6 mm 41.6 mm iris dia 24 mm 30 mm price* $250.00 $300.00 *These prices are for out right purchase price. All items (shutters, retainers, iris scales,) are priced separately. Lenses which need machine work to remount (such as lenses in barrel or in non-compatible old shutters) usually cost an additional $225.00 - $350.00 to install. New shutters may be worth more on trade. Lenses which need machine work to deal with the iris touching the back element are typically an additional $50.00 -$100.00.