Descriptions of Photo Paper

 

Nowadays, many people like printing their photo out so that can make a good memory for their whole life. So, before you printed photos you may hesitate to choosing which photo paper. And, even many people don’ t know what is photo paper. Today, I will introduce some information of photo paper.
Photo paper is a paper coated with a light-sensitive chemical formula, used for making photographic prints. When photo paper is exposed to light it captures a latent image that is then developed to form a visible image. The light-sensitive layer of the paper is called the emulsion.
History
Early photography often relied on the use of metal or glass plates instead of paper. The American Museum of Photography says that thin paper was coated with an egg white and salt solution as well as a layer of silver nitrate. The resulting single finished image appeared in brown tones, and the white areas had a yellow cast. Another later technique, developed about 1890, was Collodion paper, which utilized silver chloride and could be used to make many prints of the same image.
Modern photo paper
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. Photo paper may also be exposed to light using digital printers, 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).
Tips
Despite the introduction of digital photography, photo papers are still sold commercially. Photo 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.