Negative film
Film, also known as film, film, is an imaging equipment. Now widely used in the film is the silver halide smear on the polyester film, the film is soft, rolled into a full volume easy to use, so also known as film, when there is light on the silver halide, the silver halide conversion For the black silver, after the development process fixed on the film base, as we are common to black and white negative. Color negative film is coated with three layers of silver halide to show the three primary colors. In addition to negative film in addition to positive film and a film and so on. Early film with glass for the film base, the late 19th century plastic industry technology mature, pressed into a thin piece of plastic film to replace the glass as a base. So the film became the representative of the film. Negative film to the speed of light (din / ISO), respectively, from the lowest speed of ISO25 to ISO3200 high speed, in general, the lower the sensitivity, the more delicate quality. The most commonly used film is din21 degrees / ISO100, followed by fast film, ie din24 degrees / ISO200. Other speed of the film, due to the price, punching the technical requirements of special, in 2000 around the rise of digital photography, almost only professionals will use. ...