Shutter mechanisms
Focal plane shutters
Almost all contemporary SLRs use a focal plane shutter located in front of the film plane, which prevents the light from reaching the film even if the lens is removed, except when the shutter is actually released during the exposure. There are various designs for focal plane shutters. Typical focal plane shutters designed in the fifties and continuing through part of the 1990s consisted of cloth material with two curtains: an opening shutter curtain followed by a closing shutter curtain. During fast shutter speeds, the focal plane shutter would form a 'slit' whereby the second shutter curtain was closely following the first opening shutter curtain to produce a narrow, vertical opening, with the shutter slit moving horizontally. The slit would get narrower as shutter speeds were increased.
Other focal plane shutter designs such as the Copal, travelled vertically. These were constructed of titanium foil and were metal-bladed (resembling something like a 'venetian blind'), and resulted in faster flash synchronization. Certain horizontally travelling focal plane shutters were also constructed of titanium foil as is the case with the Nikon F, F2, F3, F4, F5 and F6 35mm SLR cameras, and the Canon F-1 camera series. A unique focal plane shutter design was the rotary shutter used in the Olympus Pen half-frame 35 mm SLR camera system. This shutter system was also titanium foil but consisted of one piece of metal with a fixed opening, and this shutter system allowed electronic flash (EF) synchronization up to and including its top shutter speed of 1/500 of a second, thereby rivaling leaf-shutter EF capabilities.
Leaf shutters — two types
Another shutter system is the leaf shutter, whereby the shutter is constructed of diaphragm-like blades and can be situated either between the lens or behind the lens. If the shutter is part of a lens assembly some other mechanism is required to ensure that no light reaches the film between exposures.
An example of a behind-the-lens leaf shutter is found in the 35 mm SLR's produced by Kodak, with their Retina Reflex camera line; Topcon, with their Auto 100; and Kowa with their SE-R and SET-R reflexes.
A primary example of a medium-format SLR with a between-the-lens leaf shutter system would be Hasselblad, with their 500C, 500CM, 500 EL-M (a motorized Hasselblad) and other models (producing a 2 1/4" square negative {or 6 cm x 6cm metric}). Hasselblads use an auxiliary shutter blind situated behind the lens mount and the mirror system to prevent the fogging of film.
Other medium-format SLRs also using leaf shutters include the now discontinued Zenza-Bronica camera system lines such as the Bronica ETRs, the ETRs'i (both producing a 6 cm. x 4.5 cm. image), the SQ and the SQ-AI (producing a 2 1/4" or 6 x 6 cm. image like the Hasselblad), and the Zenza-Bronica G system (2 1/4" x 2 3/4" inch or 6 cm. x 7 cm.). Certain Mamiya medium-format SLRs, discontinued camera systems such as the Kowa 6 and a few other camera models also used between-the-lens leaf shutters in their lens systems.
Thus, anytime a photographer purchased a lens for the Hasselblad, with the exception of the older Hasselblad 1000f and other focal-plane shutter Hasselblads; or the Zenza-Bronica ETR, ETR-S, ETR-Si, the SQ, the SQ-Ai, the SQ-B, and the G series (with the exception of older Bronica cameras such as the Bronica Deluxe, the Bronica S, the Bronica S2), or the bigger system Mamiya RB-67, RB-67 Pro, RB-67 Pro S (mechanical) and RZ (electronically controlled shutter) cameras, that lens included a leaf shutter in its lens mount.
Because leaf shutters synchronized electronic flash at all shutter speeds especially at fast shutter speeds of 1/500 of a second or faster, cameras utilizing leaf shutters were more desirable to studio photographers who used sophisticated studio electronic flash systems.
Some manufacturers of medium-format 2 1/4" SLR cameras also made leaf-shutter lenses for their focal plane shutter models. Rollei made at least two such lenses for their Rolleiflex SL-66 medium format, 2 1/4" camera, which was a focal-plane shutter SLR. Rollei later switched to a camera system of leaf-shutter design, (i.e., the 6006 and 6008 reflexes to name a few) and their current medium-format SLR's are now all of the between-the-lens shutter design.
Rotary shutter
One unusual design, the Olympus Pen half-frame 35 mm SLR system, manufactured by Olympus in Japan, used a rotary focal plane shutter mechanism which was extremely simple and elegant in design, and enabled the photographer to synchronize electronic flash at all shutter speeds, including the shutter's limit to 1/500 of a second. The camera started out meterless with the introduction of the Olympus Pen F; this camera required a two-stroke advance of the advance lever. The later models, the Olympus Pen FT and the Olympus Pen FV only required a single stroke of the film advance lever to position the film to the next frame. The Olympus Pen FT has a behind-the-lens metering system and was composed of a number of impressive optics from a 20 mm lens up to an 800 mm catadioptric (mirror) telephoto lens. The system included 'fast' lenses such as the 38mm f/1.8 Zuiko, the 40mm f/1.4 Zuiko and the 42mm f/1.2 Zuiko, all considered 'normal' lenses for this format. Olympus also made a 38mm f/3.5 macro lens, and a bellows extension attachment. There were also various lens adapters and other accessories for this camera.
As further, minor note on rotary shutters, only one other 35 mm camera system used a rotary shutter, and this camera system was the Robot Royal cameras, most of which were rangefinder 35 mm cameras. Some of these cameras were full-frame; some were half-frame, and at least one Robot camera produced an unusual square-sized image on the 35 mm frame.
Focal plane shutters
Almost all contemporary SLRs use a focal plane shutter located in front of the film plane, which prevents the light from reaching the film even if the lens is removed, except when the shutter is actually released during the exposure. There are various designs for focal plane shutters. Typical focal plane shutters designed in the fifties and continuing through part of the 1990s consisted of cloth material with two curtains: an opening shutter curtain followed by a closing shutter curtain. During fast shutter speeds, the focal plane shutter would form a 'slit' whereby the second shutter curtain was closely following the first opening shutter curtain to produce a narrow, vertical opening, with the shutter slit moving horizontally. The slit would get narrower as shutter speeds were increased.
Other focal plane shutter designs such as the Copal, travelled vertically. These were constructed of titanium foil and were metal-bladed (resembling something like a 'venetian blind'), and resulted in faster flash synchronization. Certain horizontally travelling focal plane shutters were also constructed of titanium foil as is the case with the Nikon F, F2, F3, F4, F5 and F6 35mm SLR cameras, and the Canon F-1 camera series. A unique focal plane shutter design was the rotary shutter used in the Olympus Pen half-frame 35 mm SLR camera system. This shutter system was also titanium foil but consisted of one piece of metal with a fixed opening, and this shutter system allowed electronic flash (EF) synchronization up to and including its top shutter speed of 1/500 of a second, thereby rivaling leaf-shutter EF capabilities.
Leaf shutters — two types
Another shutter system is the leaf shutter, whereby the shutter is constructed of diaphragm-like blades and can be situated either between the lens or behind the lens. If the shutter is part of a lens assembly some other mechanism is required to ensure that no light reaches the film between exposures.
An example of a behind-the-lens leaf shutter is found in the 35 mm SLR's produced by Kodak, with their Retina Reflex camera line; Topcon, with their Auto 100; and Kowa with their SE-R and SET-R reflexes.
A primary example of a medium-format SLR with a between-the-lens leaf shutter system would be Hasselblad, with their 500C, 500CM, 500 EL-M (a motorized Hasselblad) and other models (producing a 2 1/4" square negative {or 6 cm x 6cm metric}). Hasselblads use an auxiliary shutter blind situated behind the lens mount and the mirror system to prevent the fogging of film.
Other medium-format SLRs also using leaf shutters include the now discontinued Zenza-Bronica camera system lines such as the Bronica ETRs, the ETRs'i (both producing a 6 cm. x 4.5 cm. image), the SQ and the SQ-AI (producing a 2 1/4" or 6 x 6 cm. image like the Hasselblad), and the Zenza-Bronica G system (2 1/4" x 2 3/4" inch or 6 cm. x 7 cm.). Certain Mamiya medium-format SLRs, discontinued camera systems such as the Kowa 6 and a few other camera models also used between-the-lens leaf shutters in their lens systems.
Thus, anytime a photographer purchased a lens for the Hasselblad, with the exception of the older Hasselblad 1000f and other focal-plane shutter Hasselblads; or the Zenza-Bronica ETR, ETR-S, ETR-Si, the SQ, the SQ-Ai, the SQ-B, and the G series (with the exception of older Bronica cameras such as the Bronica Deluxe, the Bronica S, the Bronica S2), or the bigger system Mamiya RB-67, RB-67 Pro, RB-67 Pro S (mechanical) and RZ (electronically controlled shutter) cameras, that lens included a leaf shutter in its lens mount.
Because leaf shutters synchronized electronic flash at all shutter speeds especially at fast shutter speeds of 1/500 of a second or faster, cameras utilizing leaf shutters were more desirable to studio photographers who used sophisticated studio electronic flash systems.
Some manufacturers of medium-format 2 1/4" SLR cameras also made leaf-shutter lenses for their focal plane shutter models. Rollei made at least two such lenses for their Rolleiflex SL-66 medium format, 2 1/4" camera, which was a focal-plane shutter SLR. Rollei later switched to a camera system of leaf-shutter design, (i.e., the 6006 and 6008 reflexes to name a few) and their current medium-format SLR's are now all of the between-the-lens shutter design.
Rotary shutter
One unusual design, the Olympus Pen half-frame 35 mm SLR system, manufactured by Olympus in Japan, used a rotary focal plane shutter mechanism which was extremely simple and elegant in design, and enabled the photographer to synchronize electronic flash at all shutter speeds, including the shutter's limit to 1/500 of a second. The camera started out meterless with the introduction of the Olympus Pen F; this camera required a two-stroke advance of the advance lever. The later models, the Olympus Pen FT and the Olympus Pen FV only required a single stroke of the film advance lever to position the film to the next frame. The Olympus Pen FT has a behind-the-lens metering system and was composed of a number of impressive optics from a 20 mm lens up to an 800 mm catadioptric (mirror) telephoto lens. The system included 'fast' lenses such as the 38mm f/1.8 Zuiko, the 40mm f/1.4 Zuiko and the 42mm f/1.2 Zuiko, all considered 'normal' lenses for this format. Olympus also made a 38mm f/3.5 macro lens, and a bellows extension attachment. There were also various lens adapters and other accessories for this camera.
As further, minor note on rotary shutters, only one other 35 mm camera system used a rotary shutter, and this camera system was the Robot Royal cameras, most of which were rangefinder 35 mm cameras. Some of these cameras were full-frame; some were half-frame, and at least one Robot camera produced an unusual square-sized image on the 35 mm frame.
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