Print permanence
Encyclopedia
Print permanence refers to the longevity of printed material, especially photographs, and preservation issues. Over time, the optical density, color balance
, lustre, and other qualities of a print will degrade. The rate at which deterioration
occurs depends primarily on two main factors: the print itself, that is, the colorants used to form the image and the medium on which image resides, and the type of environment
the print is exposed to.
-based inks last generally longest when used with specific paper
types, whereas dye
-based inks can be optimal on more types of paper. Ink-jet paper types include swellable paper, porous paper, and cotton rag paper.
's Crystal Archive papers have a quoted longevity of sixty years dark storage. The stability of coupler-incorporated chromogenic prints has steadily increased since their introduction by Kodak in 1942. Very significant advances in stability were made in case of Kodak prints in 1954, 1958, and in the early 1980s. These changes can often be used for the dating of color prints, and can be correlated with manufacturing changes documented in the technical literature.
and washed. Besides rendering the image insensitive to further light exposure, fixer converts undeveloped silver salts in the emulsion into products that can easily be washed away. Effective fixing and washing removes all unexposed silver salts and leaves only a small amount of residual fixer. Any significant quantity of fixer (thiosulphate) left in the print after washing will cause the image to deteriorate over time. Many other factors play a critical role in the long-term stability of gelatin silver prints. The temperature and relative humidity of the storage environment, and the air pollutants to which a silver image is exposed are three of the most important factors.
Toning
can increase the longevity of silver-based prints by replacing or coating the metallic silver with more inert metals such as gold
, silver sulphide or selenium
.
, palladium
and gold are less prone to decay than those in silver. Amateur Photographer
's Dictionary of Photography said "Owing to the chemically inert nature of platinum, a print so made is far more permanent than any print having a silver image can be".
Indeed, the Victoria and Albert Museum
's Conservation Journal states that "...the majority of the deterioration seen in such prints is usually associated with the supports, which are often yellowed and brittle, rather than the actual image."
, ozone
and other pollutants, water
or humidity
, and high levels of light
. Though light-induced fade often gets the most publicity, greater than 90 per cent of consumer prints are stored in the dark where the effects of heat, humidity, and/or pollutants can dominate.
, Inc.
Some film companies and printer manufacturers are researching ways to increase the lifetime of their prints. While ISO or the International Organization for Standardization
has developed standards for the testing of image permanence, those standards have yet to be extended to digital print output, though the organization has signalled its intent to provide such standards.
Color balance
In photography and image processing, color balance is the global adjustment of the intensities of the colors . An important goal of this adjustment is to render specific colors – particularly neutral colors – correctly; hence, the general method is sometimes called gray balance, neutral balance,...
, lustre, and other qualities of a print will degrade. The rate at which deterioration
Deterioration
Deterioration is a term now commonly used in health care, to describe worsening of a patient's condition. It is often used as a shortened form of 'deterioration not recognised or not acted upon'. Much work to reduce harm from deterioration has been undertaken by the National Patient Safety Agency...
occurs depends primarily on two main factors: the print itself, that is, the colorants used to form the image and the medium on which image resides, and the type of environment
Surroundings
Surroundings are the area around a given physical or geographical point or place. The exact definition depends on the field. Surroundings can also be used in geography and mathematics, as well as philosophy, with the literal or metaphorically extended definition.In thermodynamics, the term is used...
the print is exposed to.
Inkjet prints
For inkjet prints, pigmentPigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...
-based inks last generally longest when used with specific paper
Paper
Paper is a thin material mainly used for writing upon, printing upon, drawing or for packaging. It is produced by pressing together moist fibers, typically cellulose pulp derived from wood, rags or grasses, and drying them into flexible sheets....
types, whereas dye
Dye
A dye is a colored substance that has an affinity to the substrate to which it is being applied. The dye is generally applied in an aqueous solution, and requires a mordant to improve the fastness of the dye on the fiber....
-based inks can be optimal on more types of paper. Ink-jet paper types include swellable paper, porous paper, and cotton rag paper.
Chromogenic color prints (silver halide prints)
The longevity of images on chromogenic color photographic papers depends on the temperature and relative humidity of the storage environment, and on the total light exposure they receive. Older chromogenic papers undergo more rapid fading compared to modern materials. For example, FujifilmFujifilm
is a multinational photography and imaging company headquartered in Tokyo, Japan.Fujifilm's principal activities are the development, production, sale and servicing of color photographic film, digital cameras, photofinishing equipment, color paper, photofinishing chemicals, medical imaging...
's Crystal Archive papers have a quoted longevity of sixty years dark storage. The stability of coupler-incorporated chromogenic prints has steadily increased since their introduction by Kodak in 1942. Very significant advances in stability were made in case of Kodak prints in 1954, 1958, and in the early 1980s. These changes can often be used for the dating of color prints, and can be correlated with manufacturing changes documented in the technical literature.
Monochrome prints
In general, black-and-white prints using either silver or carbon-based media may last longer than some colour prints. Some black-and-white prints are produced using ink-jet printers, or colour photographic paper using the RA 4 process.RA-4 process
RA-4 is Kodak's proprietary name for the chemical process most commonly used to make color photographic prints. It is used for both digital printers of the types most common today in photo labs and drug stores, and for prints made with older-type optical enlargers and manual processing...
Gelatin silver prints
To achieve a long lifespan, gelatin silver prints must be thoroughly fixedPhotographic fixer
Photographic fixer is a chemical or a mix of chemicals used in the final step in the photographic processing of film or paper. The fixer stabilises the image, removing the unexposed silver halide remaining on the photographic film or photographic paper, leaving behind the reduced metallic silver...
and washed. Besides rendering the image insensitive to further light exposure, fixer converts undeveloped silver salts in the emulsion into products that can easily be washed away. Effective fixing and washing removes all unexposed silver salts and leaves only a small amount of residual fixer. Any significant quantity of fixer (thiosulphate) left in the print after washing will cause the image to deteriorate over time. Many other factors play a critical role in the long-term stability of gelatin silver prints. The temperature and relative humidity of the storage environment, and the air pollutants to which a silver image is exposed are three of the most important factors.
Toning
Photographic print toning
In photography, toning is a method of changing the color of black-and-white photographs. In analog photography, toning is a chemical process carried out on silver-based photographic prints. This darkroom process can not be done with a color photograph and although the black-and-white photograph is...
can increase the longevity of silver-based prints by replacing or coating the metallic silver with more inert metals such as gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...
, silver sulphide or selenium
Selenium
Selenium is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium...
.
Platinum, palladium and other inert metals
Images composed of more inert metals, like platinumPlatinum
Platinum is a chemical element with the chemical symbol Pt and an atomic number of 78. Its name is derived from the Spanish term platina del Pinto, which is literally translated into "little silver of the Pinto River." It is a dense, malleable, ductile, precious, gray-white transition metal...
, palladium
Palladium
Palladium is a chemical element with the chemical symbol Pd and an atomic number of 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired...
and gold are less prone to decay than those in silver. Amateur Photographer
Amateur Photographer
Amateur Photographer is a British photography magazine, published weekly by IPC Media, a Time Warner subsidiary. The magazine provides articles on equipment reviews, photographic technique, and profiles of professional photographers.- About the magazine :...
's Dictionary of Photography said "Owing to the chemically inert nature of platinum, a print so made is far more permanent than any print having a silver image can be".
Indeed, the Victoria and Albert Museum
Victoria and Albert Museum
The Victoria and Albert Museum , set in the Brompton district of The Royal Borough of Kensington and Chelsea, London, England, is the world's largest museum of decorative arts and design, housing a permanent collection of over 4.5 million objects...
's Conservation Journal states that "...the majority of the deterioration seen in such prints is usually associated with the supports, which are often yellowed and brittle, rather than the actual image."
Environmental factors
Environmental factors that hasten the deterioration of a print include exposure to heatHeat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...
, ozone
Ozone
Ozone , or trioxygen, is a triatomic molecule, consisting of three oxygen atoms. It is an allotrope of oxygen that is much less stable than the diatomic allotrope...
and other pollutants, water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
or humidity
Humidity
Humidity is a term for the amount of water vapor in the air, and can refer to any one of several measurements of humidity. Formally, humid air is not "moist air" but a mixture of water vapor and other constituents of air, and humidity is defined in terms of the water content of this mixture,...
, and high levels of light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...
. Though light-induced fade often gets the most publicity, greater than 90 per cent of consumer prints are stored in the dark where the effects of heat, humidity, and/or pollutants can dominate.
Research and standards
Much research into image permanence has been carried out by Wilhelm Imaging ResearchWilhelm Imaging Research
Wilhelm Imaging Research, run by Henry Wilhelm, is an image testing company that provides contract testing to clients on the stability and preservation of traditional and digital color photographs and motion pictures. The company publishes brand name-specific permanence data for desktop and...
, Inc.
Some film companies and printer manufacturers are researching ways to increase the lifetime of their prints. While ISO or the International Organization for Standardization
International Organization for Standardization
The International Organization for Standardization , widely known as ISO, is an international standard-setting body composed of representatives from various national standards organizations. Founded on February 23, 1947, the organization promulgates worldwide proprietary, industrial and commercial...
has developed standards for the testing of image permanence, those standards have yet to be extended to digital print output, though the organization has signalled its intent to provide such standards.
External links
- Arthur H. Bleich (2004)."Going, going, gone! How to Create Prints that Last". Digital CameraDigital cameraA digital camera is a camera that takes video or still photographs, or both, digitally by recording images via an electronic image sensor. It is the main device used in the field of digital photography...
. - Bugner, Douglas; LaBarca, Joseph; Kopperl, David; Phillips, Jonathan; Skye, David; Baker, Irene; Cunningham, Caryn; Miller, Paige; and Kaltenbach, Thomas (February 2004). "Survey of Environmental Conditions Relative to Display of Photographs in Consumer Home". IS&T's Thirteenth International Symposium on Photofinishing Technologies. 13, 31-36. ISBN 0-89208-249-6.
- In-depth white paper (Epson)
- White paper on image permanence issues (Kodak)
- International photo industry website on image preservation
- International Organisation for Standardisation (ISO)Technical Committee 42, Photographic Standards Published and Under Development