Rolos de Filme 35mm

Photographic film is a sheet of plastic (polyester, PET, nitrocellulose or cellulose acetate) coated with an emulsion containing light-sensitive silver halide salts (bonded by gelatin) with variable crystal sizes that determine the sensitivity, contrast and resolution of the film. When the emulsion is sufficiently exposed to light (or other forms of electromagnetic radiation such as X-rays), it forms a latent (invisible) image. Chemical processes can then be applied to the film to create a visible image, in a process called film developing.

In black-and-white photographic film there is usually one layer of silver salts. When the exposed grains are developed, the silver salts are converted to metallic silver, which blocks light and appears as the black part of the film negative.

Color film uses at least three layers. Dyes, which adsorb to the surface of the silver salts, make the crystals sensitive to different colors. Typically the blue-sensitive layer is on top, followed by the green and red layers. During development, the exposed silver salts are converted to metallic silver, just as with black-and-white film. But in a color film, the by-products of the development reaction simultaneously combine with chemicals known as color couplers that are included either in the film itself or in the developer solution to form colored dyes. Because the by-products are created in direct proportion to the amount of exposure and development, the dye clouds formed are also in proportion to the exposure and development. Following development, the silver is converted back to silver salts in the bleach step. It is removed from the film in the fix step. This leaves behind only the formed color dyes, which combine to make up the colored visible image.

Red is any of a number of similar colors evoked by light consisting predominantly of the longest wavelengths discernible by the human eye, in the wavelength range of roughly 630–740 nm. Longer wavelengths just past this range are called infrared (below red) and cannot be seen by the naked eye although they can be sensed as heat. In some cultures, certain shades of red are used to symbolize anger or aggression.

It is the color of blood when it is exposed to sunlight, and it is most commonly referred to as a color of evil, love, and sometimes, though rarely, happiness.

The term 135 (ISO 1007) was introduced by Kodak in 1934 as a designation for cartridge film 35 mm (1.4 in) wide, specifically for still photography. It quickly grew in popularity, surpassing 120 film by the late 1960s to become the most popular photographic film size. Despite competition from formats such as 828, 126, 110, and APS, it remains so today.

135 camera film always comes perforated with Kodak Standard perforations. This effectively eliminates such films from being "diverted" to professional 35 mm uses, where Bell & Howell perforations are standard. 135 camera film (negative or reversal), if passed through a Western Bloc professional motion picture camera, will pass undamaged, but it will not pass with the expected and required registration accuracy for such professional uses. Eastern Bloc professional motion picture cameras generally (but not always) use Kodak Standard-perforated stocks. Most Eastern Bloc professional motion picture cameras which have been exported to Western Bloc countries have generally (but not always) been converted to Bell & Howell by skilled camera technicians in the East before such export.^{[citation needed]}

The size of the 135 film frame has been adopted by many high-end digital single-lens reflex cameras, referred to as full-frame digital SLRs.

35 mm film is the film gauge most commonly used for chemical still photography (see 135 film) and motion pictures. The name of the gauge refers to the width of the photographic film, which consists of strips 1.377 ±0.001 inches (34.98 ±0.03 mm) wide. The standard negative pulldown for movies ("single-frame" format) is four perforations per frame along both edges, which results in 16 frames per foot of film. For still photography, the standard frame has eight perforations on each side. To print an 80-minute feature film on 35 mm film stock can cost US$1,500 to $2,500.

A variety of largely proprietary gauges were devised for the numerous camera and projection systems being developed independently in the late 19th century and early 20th century, ranging from 13 mm to 75 mm (0.51–2.95 in), as well as a variety of film feeding systems. This resulted in cameras, projectors and other equipment having to be calibrated to each gauge. The 35 mm width was first used in 1892 by William Dickson and Thomas Edison, using film stock supplied by George Eastman. The 35 mm width with 4 perforations per frame became accepted as the international standard gauge in 1909, and has remained by far the dominant film gauge for image origination and projection despite challenges from smaller and larger gauges, and from novel formats, because its size allowed for a relatively good tradeoff between the cost of the film stock and the quality of the images captured. The ubiquity of 35 mm movie projectors in commercial movie theaters makes it the only motion picture format, film or video, that can be played in almost any cinema in the world.