Photographic Activity Test

Photographic Activity Test is an ISO [1] standard test detailed in ISO 18916:2007 (E). Previous versions of the standard were numbered ISO 14523:1999(E); however, it was updated and renumbered in 2007.

The test evaluates materials for archival quality and their use in photographic enclosures. Many different types of materials can be tested including: paper, boards, plastic, adhesives, pens, stickers, labels, paints and inks. The test involves incubating samples and detectors in a high-temperature, high-humidity accelerated aging environment.

Color photography

Color (or colour) photography is photography that uses media capable of reproducing colors. By contrast, black-and-white (monochrome) photography records only a single channel of luminance (brightness) and uses media capable only of showing shades of gray.

In color photography, electronic sensors or light-sensitive chemicals record color information at the time of exposure. This is usually done by analyzing the spectrum of colors into three channels of information, one dominated by red, another by green and the third by blue, in imitation of the way the normal human eye senses color. The recorded information is then used to reproduce the original colors by mixing various proportions of red, green and blue light (RGB color, used by video displays, digital projectors and some historical photographic processes), or by using dyes or pigments to remove various proportions of the red, green and blue which are present in white light (CMY color, used for prints on paper and transparencies on film).

Monochrome images which have been "colorized" by tinting selected areas by hand or mechanically or with the aid of a computer are "colored photographs", not "color photographs". Their colors are not dependent on the actual colors of the objects photographed and may be inaccurate.

The foundation of virtually all practical color processes, the three-color method was first suggested in an 1855 paper by Scottish physicist James Clerk Maxwell, with the first color photograph produced by Thomas Sutton for a Maxwell lecture in 1861. Color photography has been the dominant form of photography since the 1970s, with monochrome photography mostly relegated to niche markets such as art photography.

Conservation and restoration of film

The conservation and restoration of film is the physical care and treatment of film-based materials (plastic supports). These include photographic materials and motion picture.

Conservation and restoration of photographs

The Conservation and restoration of photographs is the study of the physical care and treatment of photographic materials. It covers both efforts undertaken by photograph conservators, librarians, archivists, and museum curators who manage photograph collections at a variety of cultural heritage institutions, as well as steps taken to preserve collections of personal and family photographs. It is an umbrella term that includes both preventative preservation activities such as environmental control and conservation techniques that involve treating individual items. Both preservation and conservation require an in-depth understanding of how photographs are made, and the causes and prevention of deterioration. Conservator-restorers use this knowledge to treat photographic materials, stabilizing them from further deterioration, and sometimes restoring them for aesthetic purposes.

While conservation can improve the appearance of a photograph, image quality is not the primary purpose of conservation. Conservators will try to improve the visual appearance of a photograph as much as possible, while also ensuring its long-term survival and adhering the profession's ethical standards. Photograph conservators also play a role in the field of connoisseurship. Their understanding of the physical object and its structure makes them uniquely suited to a technical examination of the photograph, which can reveal clues about how, when, and where it was made.

Photograph preservation is distinguished from digital or optical restoration, which is concerned with creating and editing a digital copy of the original image rather than treating the original photographic material. Photograph preservation does not normally include moving image materials, which by their nature require a very different approach. Film preservation concerns itself with these materials.

Hand-colouring of photographs

Hand-colouring (or hand-coloring) refers to any method of manually adding colour to a black-and-white photograph, generally either to heighten the realism of the photograph or for artistic purposes. Hand-colouring is also known as hand painting or overpainting.

Typically, watercolours, oils, crayons or pastels, and other paints or dyes are applied to the image surface using brushes, fingers, cotton swabs or airbrushes. Hand-coloured photographs were most popular in the mid- to late-19th century before the invention of colour photography and some firms specialised in producing hand-coloured photographs.

Photograph conservator

A photograph conservator is a professional who examines, documents, researches, and treats photographs, including documenting the structure and condition of art works through written and photographic records, monitoring conditions of works in storage and exhibition and transit environments. This person also performs all aspects of the treatment of photographs and related artworks with adherence to the Code of Ethics outlined by the American Institute for Conservation.

ISO standards by standard number
1–9999
10000–19999
20000+

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