Printing converts the negative image of the film into a positive image on paper. Light is shone through the film onto light-sensitive paper. Passing the light through lenses makes the image larger. The print is then developed and fixed just as the film was.
Photographic paper is a paper coated with a light-sensitive chemical formula, used for making photographic prints. When photographic paper is exposed to light, it captures a latent image that is then developed to form a visible image; with most papers the image density from exposure can be sufficient to not require further development, aside from fixing and clearing, though latent exposure is also usually present. The light-sensitive layer of the paper is called the emulsion. The most common chemistry was based on silver salts but other alternatives have also been used.
The print image is traditionally produced by interposing a photographic negative between the light source and the paper, either by direct contact with a large negative (forming a contact print) or by projecting the shadow of the negative onto the paper (producing an enlargement). The initial light exposure is carefully controlled to produce a gray scale image on the paper with appropriate contrast and gradation. Photographic paper may also be exposed to light using digital printers such as the Light-jet, with a camera (to produce a photographic negative), by scanning a modulated light source over the paper, or by placing objects upon it (to produce a photogram).
Despite the introduction of digital photography, photographic papers are still sold commercially. Photographic papers are manufactured in numerous standard sizes, paper weights and surface finishes. A range of emulsions are also available that differ in their light sensitivity, color response and the warmth of the final image. Color papers are also available for making color images.
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