Positive (photography) in the context of "Reversal film"

Photography is the art, application, and practice of creating images by recording light, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film. It is employed in many fields of science, manufacturing (e.g., photolithography), and business, as well as its more direct uses for art, film and video production, recreational purposes, hobby, and mass communication. A person who operates a camera to capture or take photographs is called a photographer, while the captured image, also known as a photograph, is the result produced by the camera.

Typically, a lens is used to focus the light reflected or emitted from objects into a real image on the light-sensitive surface inside a camera during a timed exposure. With an electronic image sensor, this produces an electrical charge at each pixel, which is electronically processed and stored in a digital image file for subsequent display or processing. The result with photographic emulsion is an invisible latent image, which is later chemically "developed" into a visible image, either negative or positive, depending on the purpose of the photographic material and the method of processing. A negative image on film is traditionally used to photographically create a positive image on a paper base, known as a print, either by using an enlarger or by contact printing.

Photographic processing or photographic development is the chemical means by which photographic film or paper is treated after photographic exposure to produce a negative or positive image. Photographic processing transforms the latent image into a visible image, makes this permanent and renders it insensitive to light.

All processes based upon the gelatin silver process are similar, regardless of the film or paper's manufacturer. Exceptional variations include instant films such as those made by Polaroid and thermally developed films. Kodachrome required Kodak's proprietary K-14 process. Kodachrome film production ceased in 2009, and K-14 processing is no longer available as of December 30, 2010. Ilfochrome materials use the dye destruction process. Deliberately using the wrong process for a film is known as cross processing.

Instant film is a type of photographic film that was introduced by Polaroid Corporation to produce a visible image within minutes or seconds of the photograph's exposure. The film contains the chemicals needed for developing and fixing the photograph, and the camera exposes and initiates the developing process after a photo has been taken.

In earlier Polaroid instant cameras the film is pulled through rollers, breaking open a pod containing a reagent that is spread between the exposed negative and receiving positive sheet. This film sandwich develops for some time after which the positive sheet is peeled away from the negative to reveal the developed photo. In 1972, Polaroid introduced integral film, which incorporated timing and receiving layers to automatically develop and fix the photo without any intervention from the photographer.

The paper negative process consists of using a negative printed on paper (either photographically or digitally) to create the final print of a photograph, as opposed to using a modern negative on a film base of cellulose acetate. The plastic acetate negative (which is what modern films produce) enables the printing of a very sharp image intended to be as close a representation of the actual subject as is possible. By using a negative based on paper instead, there is the possibility of creating a more ethereal image, simply by using a type of paper with a very visible grain, or by drawing on the paper or distressing it in some way.

One of the original forms of photography was based on the paper negative process. William Henry Fox Talbot's paper negative process, which was used to create his work "The Pencil of Nature", used a negative created on paper treated with silver salts, which was exposed in a camera obscura to create the negative and then contact printed on a similar paper to produce a positive image.

Cinematography (from Ancient Greek κίνημα (kínēma) 'movement' and γράφειν (gráphein) 'to write, draw, paint, etc.') is the art of motion picture (and more recently, electronic video camera) photography.

Cinematographers use a lens to focus reflected light from objects into a real image that is transferred to some image sensor or light-sensitive material inside the movie camera. These exposures are created sequentially and preserved for later processing and viewing as a motion picture. Capturing images with an electronic image sensor produces an electrical charge for each pixel in the image, which is electronically processed and stored in a video file for subsequent processing or display. Images captured with photographic emulsion result in a series of invisible latent images on the film stock, which are chemically "developed" into a visible image. The images on the film stock are projected for viewing in the same motion picture.