Photo paper is a paper carrier coated with a light-sensitive chemical, which is mainly used for the production of photo prints. It is exposed in a controlled manner by bringing the negative directly into contact with the paper to make a contact stamp and using a magnifying glass. This is done by exposing the camera type to the negative. Photo paper is usually processed using a silver agar process to produce visible images. You can also find the best coated paper via https://arrowpaper.com.au/collections/coated-papers.
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There are several types of photo paper, which are usually classified according to their use:
1. Document used for the negative-positive process which includes all common black and white paper and chromogenic colored paper.
2. Document used for the positive-positive process where the "film" corresponds to the final image.
3. Paper used for the positive-on-film-on-paper process in which the positive image is enlarged and copied onto photo paper.
The inner structure of the photo paper consists of a light sensitive emulsion solution. Contains a suspension of halogen salts in suspension in a colloidal material. In the past, linen was used as the main material. Resin or polyester coated paper is used today for black and white paper.
For black and white images, the emulsion is sensitive to blue and green light, but this process remains inactive when it has a wavelength above 600 nm. Therefore, images can be created in an environment consisting of red-orange lighting. For this reason, photographers, whether amateur or professional, develop all the negativity in tight lighting situations.