Film stock is an analog medium that is used for recording motion pictures or animation. It is recorded on by a movie camera, developed, edited, and projected onto a screen using a movie projector. It is a strip or sheet of transparent plastic film base coated on one side with a gelatin emulsion containing microscopically small light-sensitive silver halide crystals. The sizes and other characteristics of the crystals determine the sensitivity, contrast and resolution of the film. The emulsion will gradually darken if left exposed to light, but the process is too slow and incomplete to be of any practical use. Instead, a very short exposure to the image formed by a camera lens is used to produce only a very slight chemical change, proportional to the amount of light absorbed by each crystal. This creates an invisible latent image in the emulsion, which can be chemically developed into a visible photograph. In addition to visible light, all films are sensitive to X-rays and high-energy particles. Most are at least slightly sensitive to invisible ultraviolet (UV) light. Some special-purpose films are sensitive into the infrared (IR) region of the spectrum.
35 mm film is a film gauge used in filmmaking, and the film standard. In motion pictures that record on film, 35 mm is the most commonly used gauge. The name of the gauge is not a direct measurement, and refers to the nominal width of the 35 mm format photographic film, which consists of strips 1.377 ± 0.001 inches (34.976 ± 0.025 mm) wide. The standard image exposure length on 35 mm for movies is four perforations per frame along both edges, which results in 16 frames per foot of film.
16 mm film is a historically popular and economical gauge of film. 16 mm refers to the width of the film ; other common film gauges include 8 mm and 35 mm. It is generally used for non-theatrical film-making, or for low-budget motion pictures. It also existed as a popular amateur or home movie-making format for several decades, alongside 8 mm film and later Super 8 film. Eastman Kodak released the first 16 mm "outfit" in 1923, consisting of a camera, projector, tripod, screen and splicer, for US$335. RCA-Victor introduced a 16 mm sound movie projector in 1932, and developed an optical sound-on-film 16 mm camera, released in 1935.
8 mm film is a motion picture film format in which the film strip is eight millimetres (0.31 in) wide. It exists in two main versions – the original standard 8 mm film, also known as regular 8 mm, and Super 8. Although both standard 8 mm and Super 8 are 8 mm wide, Super 8 has a larger image area because of its smaller and more widely spaced perforations.
Super 8 mm film is a motion-picture film format released in 1965 by Eastman Kodak as an improvement over the older "Double" or "Regular" 8 mm home movie format.
135 film, more popularly referred to as 35 mm film or 35 mm, is a format of photographic film with a film gauge of 35 mm (1.4 in) loaded into a standardized type of magazine for use in 135 film cameras.
DX encoding is a standard for marking 35 mm and APS photographic film and film cartridges, originally introduced by Kodak in 1983. It includes multiple markings, which are a latent image barcode on the bottom edge of the film, below the sprocket holes, a conductive pattern on the cartridge used by automatic cameras, and a barcode on the cartridge read by photo-finishing machines.
The DX number is a number which uniquely identifies the type and manufacturer (sensitizer) of a film emulsion. These DX numbers were assigned by the International Imaging Industry Association (I3A), which published and sold a proprietary list of DX numbers for APS and 135 film yearly or as needed. The last edition of the list, entitled DX Codes for 135-Size Film, was published in January 2009.
A movie camera is a type of photographic camera that rapidly takes a sequence of photographs, either onto film stock or an image sensor, in order to produce a moving image to display on a screen. In contrast to the still camera, which captures a single image at a time, the movie camera takes a series of images by way of an intermittent mechanism or by electronic means; each image is a frame of film or video. The frames are projected through a movie projector or a video projector at a specific frame rate to show the moving picture. When projected at a high enough frame rate, the persistence of vision allows the eyes and brain of the viewer to merge the separate frames into a continuous moving picture.
In photography, reversal film or slide film is a type of photographic film that produces a positive image on a transparent base. Instead of negatives and prints, reversal film is processed to produce transparencies or diapositives. Reversal film is produced in various sizes, from 35 mm to roll film to 8×10 inch sheet film.
Negative pulldown is the manner in which an image is exposed on a film stock, described by the number of film perforations spanned by an individual frame. It can also describe whether the image captured on the negative is oriented horizontally or vertically. Changing the number of exposed perforations allows a cinematographer to change both the aspect ratio of the image and the size of the area on the film stock that the image occupies.
Film perforations, also known as perfs and sprocket holes, are the holes placed in the film stock during manufacturing and used for transporting and steadying the film. Films may have different types of perforations depending on film gauge, film format, and intended usage. Perforations are also used as a standard measuring reference within certain camera systems to refer to the size of the frame.
A film base is a transparent substrate which acts as a support medium for the photosensitive emulsion that lies atop it. Despite the numerous layers and coatings associated with the emulsion layer, the base generally accounts for the vast majority of the thickness of any given film stock. Since the late 19th century, there have been three major types of film base in use: nitrate, acetate, and polyester.
Color motion picture film refers both to unexposed color photographic film in a format suitable for use in a motion picture camera, and to finished motion picture film, ready for use in a projector, which bears images in color.
A cue mark, also known as a cue dot, a cue blip, a changeover cue or simply a cue, is a visual indicator used with motion picture film prints, usually placed in the upper right corner of a film frame. Cue dots are also used as a visual form of signalling on television broadcasts.
Standard 8 mm film, also known as Regular 8 mm, Double 8 mm, Double Regular 8 mm film, or simply as Standard 8 or Regular 8, is an 8 mm film format originally developed by the Eastman Kodak company and released onto the market in 1932.
In bipack color photography for motion pictures, two strips of black-and-white 35 mm film, running through the camera emulsion to emulsion, are used to record two regions of the color spectrum, for the purpose of ultimately printing the images, in complementary colors, superimposed on one strip of film. The result is a multicolored projection print that reproduces a useful but limited range of color by the subtractive color method. Bipack processes became commercially practical in the early 1910s when Kodak introduced duplitized film print stock, which facilitated making two-color prints.
Kodak Professional T-MAX Film is a continuous tone, panchromatic, tabular-grain black and white negative film originally developed and manufactured by Eastman Kodak since 1986. It is still manufactured by Eastman Kodak but distributed and marketed by Kodak Alaris, as with other products under Kodak Professional banner.
Test film are rolls or loops or slides of photographic film used for testing the quality of equipment. Equipment to be tested could include: telecine, motion picture film scanner, Movie projectors, Image scanners, film-out gear, Film recorders and Film scanners.
