In 1889, celluloid-based transparent, flexible 35mm film was invented by the Rev. Hannibal Goodwin [1824-1901]. He conceived the idea of a flexible, unbreakable material upon which to mount the slides he liked to use in his Sunday School, and, with a license from the Newark Celluloid Varnish Co., set to work to prove that celluloid could be thinned and flattened to use as an image base. Goodwin's invention was promoted by George Eastman on a wide-scale for commercial use.
The first decade of motion picture production saw a mixed bag of film formats and sprocket holes and hardly any standardization. William Kennedy Laurie Dickson [1860-1935], working for Thomas Alva Edison, used 4-perf 35mm film [1.33:1] for his camera, the Kinetograph , his peephole machine, the Kinetoscope , and his projector, the Vitascope [built by Thomas Armat and C. Francis Jenkins in 1895 and sold to Edison in 1896]. The Brothers Lumière used 1-perf 35mm for their Cinématographe . Others used films with a width of 11mm, 24mm, 28mm, 50mm, 62mm, etc.
See also: Wikipedia [List of Film Formats]
In 1907, a voluntary agreement was reached, which became known as the Motion Picture Patents Agreement of 1907. 35mm and certain other specifications were defined as a standard motion picture film: 35mm in width, 4 perforations along both sides of each frame [4:3 or 1.33:1] and a film speed of circa 16 frames per second. In 1927, the Academy of Motion Picture Arts and Sciences officially made 1.33:1 the industry standard, the Academy Aperture.
'The average camera speed is two turns per second, or one foot of film per second. There are approximately 16 images per foot, and the above speed is used invariably, and projection should be at this speed except in scenes where the tempo of the action requires speeding up of the objects, as, for example, in a fight scene. "Average" speed in this case would be too slow. In comedy various speeds are used from normal to stop motion, in order to obtain desired effects. Of course if a projectionist speeds up to 100, where the scene was shot at 60, in order to get through with the show, no human eye will be able to stand the strain of watching objects moving at that speed. It will ruin every effort made by the producer, director and staff to put their best efforts before the public.' [Victor Milner, 1923.]
'Regarding our opinion as to the correct camera speeds, we wish to state that this matter has been discussed from time to time among our members and it is the consensus of opinion of our Society that the correct camera speed is sixteen pictures per second or sixty feet per minute. This speed has been used for years by practically all members of the profession, slower speeds only being resorted to, to secure certain comedy and dramatic effects. Over-speeding has only been used where certain directors have attempted to combat the excessive projection speeds which exhibitors have adopted to "turn over their audiences" in the shortest possible time. We are opposed to any taking speed in excess of sixty feet per minute.' [John W. Boyle, American Society of Cinematographers, 1925.]
The advent of sound in 1929 at first necessitated the squaring of the frame [1.16:1] to allow room for a soundtrack. In 1931 there was a consensus among major studios as to the exact camera and projector aperture dimensions for 35mm sound films. This consensus provided a modification of the Academy Aperture to 1.37 width to 1.0 height [1.37:1], which was very close to the original 1.33:1 silent screen shape. The 1.37:1 aspect ratio remained unchallenged until 1952.
In 1948 Eastman Kodak introduced 35mm tri-acetate safety base film for the motion picture industry to replace the flammable cellulose nitrate base. The conversion from nitrate to safety base was completed in 1952.
This refers to the number of film perforations that each film frame occupies, as well as whether they are pulled horizontally or vertically. The most common film pulldowns are 4-perf and 3-perf, the latter of which is usually used in conjunction with Super 35. 2-perf, used in Techniscope in the 1960's, is enjoying a resurgence due to the birth of digital intermediate techniques eliminating the need for optical lab work. Vertical pulldown is overwhelmingly the dominant axis of motion, although horizontal pulldown is used in IMAX, VistaVision [still in use for some visual effects work], and in consumer and professional still cameras. [From the Wikipedia website.]
In these days of the HD vs. Film debate, 3-perf is the future of film origination: image quality up, cost down. Slight modifications to cameras and rush projectors induce considerable reduction of film origination costs. Any off-the-shelf 35mm raw stock can be used in a 3-perf camera [after modification of the regular 4-perf pulldown claw movement]. By eliminating the interimage waste, 3-perf pulldown reduces negative, rush and inter-positive stock consumption as well as their associated processing costs by 25%.
Drawing by Max Smith
Like Super 16, 3-perf negatives must go through either a 'Digital' or 'Straight Optical' transfer to deliver standard 4-perf prints for theatre distribution. Since the 'original negative to release print' path is no longer following the 'contact-print' process, it is no longer necessary to preserve - and waste - the sound track space, on the original image. It becomes wiser to shoot Super 35 and use the complete 'perf to perf' silver halide real estate. The Super 35 1.85:1 images occupy 324 mm² instead of the 273 mm² stored on a 1.85 cropped Academy frame [a 25% bonus].
3-perf brings a 33% increase of the apparent length of the magazines: a 400 foot roll lasts for about 6 minutes instead of 4½ in 4-perf. Because of the larger image - for the same apparent graininess - faster stocks can be used, which means lighter lighting fixtures. A two hour film - considering an average twelve for one ratio - can be made with 220 rolls instead of 330, i.e. 27,000 meters instead of 40,000. [From the Aaton website.]
See also: Super 35
2-perf camera systems use only 2 perforations per frame on 35mm film, which gives an aspect ratio close to the 2.39:1 aspect ratio used in anamorphic prints. It was first proposed conceptually around 1930, but was not put into practice until 1960, when Techniscope was developed at Technicolor's Italian branch.
The Techniscope format uses a 2-perf negative pulldown per frame, instead of the standard 4-perf frame usually exposed in 35mm film photography. Techniscope's 2.33:1 aspect ratio is easily cropped to the 2.35:1 widescreen ratio, because it uses half the amount of 35mm film stock and standard spherical lenses. [In 1970, the SMPTE revised the 2.35:1 aspect ratio to 2.39:1 (now known as 2.40:1), however, before standardization, most Techniscope films were photographed and released in the 2.35:1 aspect ratio.]
Thus, Techniscope release prints are made by anamorphosizing and enlarging each frame by a factor of two. Because 2-perf is not a release format [all films still have to be released in 4-perf to theatres], producers will often elect to do a high quality scan to video, an optical blowup or, ideally, use the digital intermediate post-production method to eliminate optical blowups and thus improve quality.
Drawing by Max Smith
While in the recent past, some companies have offered custom conversions of camera equipment to 2-perf, it is now clear that camera manufacturers are supporting the format. ARRI made 2-perf movement blocks for their Arricam and Arriflex 235 cameras, while Aaton's Penelope camera is the first camera specifically designed for 2-perf usage [as well as 3-perf].
Aaton's Penelope: 3-perf & 2-perf
See also: Techniscope
See also: Aaton Penelope