Contact print
Encyclopedia
A contact print is a photographic image
produced from film
; sometimes from a film negative
, and sometimes from a film positive. The defining characteristic of a contact print is that the photographic result is made by exposing through the film negative or positive, onto a light sensitive material that is pressed tightly to the film.
In the dark, or under a safe light, an exposed and developed piece of photographic film
is placed emulsion
side down, against a piece of photographic paper
. Light
is briefly shone through the negative. Then, the paper is developed into a contact print. The image in the emulsion has been pressed as close as possible to the photosensitive
paper. An exposure box device called a contact printer or a printing frame is sometimes used within a light-controlled space called a darkroom
. Enlarger
s can also be used for this process.
. Below the diffuser is a switch-controlled electric light source. A hinged top-cover keeps the materials in close contact and reduces or eliminates the amount of stray light allowed into the darkroom. Ansel Adams
describes procedures for making contact prints using ordinary lighting in his book, The Print.
The contact printer is used to expose the negative's image onto the paper for a few seconds, creating an invisible latent image on the paper. The operator may use a manual switch and count off the seconds himself, or he may use an electric timer switch.
The black and white gelatin-silver process
may be done using a red "safe light" for darkroom illumination. The contact printer may also contain a safe light so that the negative can be examined before the photographic paper is laid upon it.
After exposure, the paper is processed using chemicals in the darkroom to produce the final print. The paper must be placed in a film developer bath, a stop bath, fixer, and finally the hypo-eliminator bath, in that order. Failure to adhere precisely to this process will result in a poor-quality final image with a variety of issues.
) and 120 (2 1/4 film rolls) in order to aid in the selection of images for further enlargement, and for cataloging and identification purposes. For 120 roll film
(once a common negative size for popular cameras) and larger film, contact prints are often used to determine the final print size. In medium and large format
photography, contact prints are prized for their extreme fidelity to the negative, with exquisite detail that can be seen with the use of a magnifying glass
. A disadvantage to using contact prints in the fine-arts is the laboriousness of modifying exposure selectively, when the use of an enlarger
can achieve the same purpose.
Because light does not pass any significant distance through the air or through lenses
in going from the negative to the print, the contact process ideally preserves all the detail that is present in the negative. However, the exposure value
(EV) range, the variation from darkest to lightest regions, is inherently greater in negatives than in prints.
Some alternative processes or non-silver processes, such as van Dyke
and cyanotype
printing, must be contact printed. Medium or large format negatives are almost always used for these types of printing. Images from smaller formats may be transferred to a larger format negative for this purpose.
, and in printed circuit
manufacturing.
The contact exposure process usually refers to a film negative used in conjunction with printing paper, but the process may be used with any transparent or translucent original image printed by contact onto a light sensitive material. Negatives or positives on film or even paper may for various purposes be used to make contact exposures onto different films and papers. Intermediary products such as internegatives, interpositives, enlarged negatives, and contrast controlling masks are often made using contact exposures.
Computer screens and other electronic display devices provide an alternative approach to contact printing. A permanent image (negative, positive film or transparency, or translucent original) is not used, instead the light sensitive material is exposed directly to the display device in a dark room for a controllable duration . The resulting image generated by this mixed digital/analogue technique has been coined "laptopogram". While limited by the image display device resolution, which can be much inferior to film negatives, the widespread use of electronic displays provides great potential to this unorthodox contact printing method.
cassettes, 35 mm (24×36 mm images), and 120/220 roll film
(6 cm), are useful for evaluation of exposure, composition, and subject.
It is cheaper and easier to avoid making conventional prints of all the exposures with an enlarger
; the photographer prints only the best negatives. Selection is usually made using a loupe
— a special magnifying glass
with a transparent base — to examine the tiny prints, still aligned as they are on the negative strips. Negatives themselves can be examined with a loupe, but blacks and whites are the reverse of what is seen through the view finder (hence: a negative), which makes it slightly more difficult to interpret the images. Contact sheets can easily be stored in files in the dark, along with the negatives. A stack of conventional prints is much thicker.
Image
An image is an artifact, for example a two-dimensional picture, that has a similar appearance to some subject—usually a physical object or a person.-Characteristics:...
produced from film
Photographic film
Photographic film is a sheet of plastic coated with an emulsion containing light-sensitive silver halide salts with variable crystal sizes that determine the sensitivity, contrast and resolution of the film...
; sometimes from a film negative
Negative (photography)
In photography, a negative may refer to three different things, although they are all related.-A negative:Film for 35 mm cameras comes in long narrow strips of chemical-coated plastic or cellulose acetate. As each image is captured by the camera onto the film strip, the film strip advances so that...
, and sometimes from a film positive. The defining characteristic of a contact print is that the photographic result is made by exposing through the film negative or positive, onto a light sensitive material that is pressed tightly to the film.
In the dark, or under a safe light, an exposed and developed piece of photographic film
Photographic film
Photographic film is a sheet of plastic coated with an emulsion containing light-sensitive silver halide salts with variable crystal sizes that determine the sensitivity, contrast and resolution of the film...
is placed emulsion
Emulsion
An emulsion is a mixture of two or more liquids that are normally immiscible . Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms colloid and emulsion are sometimes used interchangeably, emulsion is used when both the dispersed and the...
side down, against a piece of photographic paper
Photographic paper
Photographic paper is paper coated with light-sensitive chemicals, used for making photographic prints.Photographic paper is exposed to light in a controlled manner, either by placing a negative in contact with the paper directly to produce a contact print, by using an enlarger in order to create a...
. 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...
is briefly shone through the negative. Then, the paper is developed into a contact print. The image in the emulsion has been pressed as close as possible to the photosensitive
Photosensitivity
Photosensitivity is the amount to which an object reacts upon receiving photons, especially visible light.- Human medicine :Sensitivity of the skin to a light source can take various forms. People with particular skin types are more sensitive to sunburn...
paper. An exposure box device called a contact printer or a printing frame is sometimes used within a light-controlled space called a darkroom
Darkroom
A darkroom is a room that can be made completely dark to allow the processing of light sensitive photographic materials, including photographic film and photographic paper. Darkrooms have been created and used since the inception of photography in the early 19th century...
. Enlarger
Enlarger
An enlarger is a specialized transparency projector used to produce photographic prints from film or glass negatives using the gelatin silver process, or from transparencies.-Construction:...
s can also be used for this process.
Basic tools
One or more negatives are placed in intimate contact with a sheet of sensitized photographic paper. The negative and the photographic paper are then placed, negative side down, onto the top transparent glass plate of the exposure box. Within the box and below the top plate is a translucent light diffuser made from frosted glassFrosted glass
Frosted glass is produced by the sandblasting or acid etching of clear sheet glass. It has the effect of rendering the glass translucent by scattering of light during transmission, thus blurring images while still transmitting light.Applications:...
. Below the diffuser is a switch-controlled electric light source. A hinged top-cover keeps the materials in close contact and reduces or eliminates the amount of stray light allowed into the darkroom. Ansel Adams
Ansel Adams
Ansel Easton Adams was an American photographer and environmentalist, best known for his black-and-white photographs of the American West, especially in Yosemite National Park....
describes procedures for making contact prints using ordinary lighting in his book, The Print.
The contact printer is used to expose the negative's image onto the paper for a few seconds, creating an invisible latent image on the paper. The operator may use a manual switch and count off the seconds himself, or he may use an electric timer switch.
The black and white gelatin-silver process
Gelatin-silver process
The gelatin silver process is the photographic process used with currently available black-and-white films and printing papers. A suspension of silver salts in gelatin is coated onto a support such as glass, flexible plastic or film, baryta paper, or resin-coated paper...
may be done using a red "safe light" for darkroom illumination. The contact printer may also contain a safe light so that the negative can be examined before the photographic paper is laid upon it.
After exposure, the paper is processed using chemicals in the darkroom to produce the final print. The paper must be placed in a film developer bath, a stop bath, fixer, and finally the hypo-eliminator bath, in that order. Failure to adhere precisely to this process will result in a poor-quality final image with a variety of issues.
Proof sheets
Since this process produces neither enlargements nor reductions, the image on the print is exactly the same size as the image on the negative. Contact prints are used to produce proof sheets from entire rolls of 35 mm negative (from 135 film cassettes135 film
The term 135 was introduced by Kodak in 1934 as a designation for cartridge film wide, specifically for still photography. It quickly grew in popularity, surpassing 120 film by the late 1960s to become the most popular photographic film format...
) and 120 (2 1/4 film rolls) in order to aid in the selection of images for further enlargement, and for cataloging and identification purposes. For 120 roll film
120 film
120 is a film format for still photography introduced by Kodak for their Brownie No. 2 in 1901. It was originally intended for amateur photography but was later superseded in this role by 135 film...
(once a common negative size for popular cameras) and larger film, contact prints are often used to determine the final print size. In medium and large format
Large format
Large format refers to any imaging format of 4×5 inches or larger. Large format is larger than "medium format", the 6×6 cm or 6×9 cm size of Hasselblad, Rollei, Kowa, Pentax etc cameras , and much larger than the 24×36 mm frame of 35 mm format.The main advantage...
photography, contact prints are prized for their extreme fidelity to the negative, with exquisite detail that can be seen with the use of a magnifying glass
Magnifying glass
A magnifying glass is a convex lens that is used to produce a magnified image of an object. The lens is usually mounted in a frame with a handle ....
. A disadvantage to using contact prints in the fine-arts is the laboriousness of modifying exposure selectively, when the use of an enlarger
Enlarger
An enlarger is a specialized transparency projector used to produce photographic prints from film or glass negatives using the gelatin silver process, or from transparencies.-Construction:...
can achieve the same purpose.
Because light does not pass any significant distance through the air or through lenses
Lens (optics)
A lens is an optical device with perfect or approximate axial symmetry which transmits and refracts light, converging or diverging the beam. A simple lens consists of a single optical element...
in going from the negative to the print, the contact process ideally preserves all the detail that is present in the negative. However, the exposure value
Exposure value
In photography, exposure value denotes all combinations of a camera's shutter speed and relative aperture that give the same exposure. In an attempt to simplify choosing among combinations of equivalent camera settings, the concept was developed by the German shutter manufacturer in the 1950s...
(EV) range, the variation from darkest to lightest regions, is inherently greater in negatives than in prints.
Finished prints
When large format film is contact printed to create finished work, it is possible, but not easy, to use local controls to interpret the image on the negative. "Burning" and "dodging" (either increasing the amount of light that one area of the print receives, or decreasing the amount of light in order to achieve the ideal tonal range in a particular area) require painstaking work with photographic masks, or the use of a production contact printing machine (Arkay, Morse, Burke and James are manufacturers who make contact printing machines).Some alternative processes or non-silver processes, such as van Dyke
Van dyke brown
Van Dyke Brown is an early photographic printing process. The process was so named due to the similarity of the print color to that of a brown oil paint named for Flemish painter Van Dyck.-Printing:...
and cyanotype
Cyanotype
Cyanotype is a photographic printing process that gives a cyan-blue print. The process was popular in engineering circles well into the 20th century. The simple and low-cost process enabled them to produce large-scale copies of their work, referred to as blueprints...
printing, must be contact printed. Medium or large format negatives are almost always used for these types of printing. Images from smaller formats may be transferred to a larger format negative for this purpose.
Production tools
Contact printing machines are more elaborate devices than the more familiar and widely available contact printing frames. They typically combine in a box the light source, intermediate glass stages, and a final glass stage for the negative and paper to be placed upon, as well as an elastic pressure plate to keep the negative and the paper in tight contact. Dodging can be accomplished by placing fine tissue paper on the intermediate glass stages between the light source and the negative/paper sandwich to modify the exposure locally. The benefit to such time intensive techniques is the ability to then make multiple prints with negligible variation, at full production speed.Other valuable uses for the technique
Contact printing was also once used in photolithographyPhotolithography
Photolithography is a process used in microfabrication to selectively remove parts of a thin film or the bulk of a substrate. It uses light to transfer a geometric pattern from a photomask to a light-sensitive chemical "photoresist", or simply "resist," on the substrate...
, and in printed circuit
Printed circuit
Printed circuit may refer to:* Printed circuit board* Printed Circuit Corporation, an electronics manufacturer...
manufacturing.
The contact exposure process usually refers to a film negative used in conjunction with printing paper, but the process may be used with any transparent or translucent original image printed by contact onto a light sensitive material. Negatives or positives on film or even paper may for various purposes be used to make contact exposures onto different films and papers. Intermediary products such as internegatives, interpositives, enlarged negatives, and contrast controlling masks are often made using contact exposures.
Computer screens and other electronic display devices provide an alternative approach to contact printing. A permanent image (negative, positive film or transparency, or translucent original) is not used, instead the light sensitive material is exposed directly to the display device in a dark room for a controllable duration . The resulting image generated by this mixed digital/analogue technique has been coined "laptopogram". While limited by the image display device resolution, which can be much inferior to film negatives, the widespread use of electronic displays provides great potential to this unorthodox contact printing method.
Artistic and practical considerations
Photographers praise the beautiful intermediate gray or color gradation that results from making prints this way. Each print is necessarily the same size as the corresponding image on the negative. This makes contact prints from large-format negatives, especially 5x7 inch and larger, most usable for fine-art work. Smaller contact prints, from films and formats such as 135 film135 film
The term 135 was introduced by Kodak in 1934 as a designation for cartridge film wide, specifically for still photography. It quickly grew in popularity, surpassing 120 film by the late 1960s to become the most popular photographic film format...
cassettes, 35 mm (24×36 mm images), and 120/220 roll film
Roll film
Rollfilm or roll film is any type of spool-wound photographic film protected from white light exposure by a paper backing, as opposed to film which is protected from exposure and wound forward in a cartridge. Confusingly, roll film was originally often referred to as "cartridge" film because of its...
(6 cm), are useful for evaluation of exposure, composition, and subject.
It is cheaper and easier to avoid making conventional prints of all the exposures with an enlarger
Enlarger
An enlarger is a specialized transparency projector used to produce photographic prints from film or glass negatives using the gelatin silver process, or from transparencies.-Construction:...
; the photographer prints only the best negatives. Selection is usually made using a loupe
Loupe
A loupe is a simple, small magnification device used to see small details more closely. Unlike a magnifying glass, a loupe does not have an attached handle, and its focusing lens are contained in an opaque cylinder or cone. Loupes are also called hand lenses .- Optics :Three basic types of loupes...
— a special magnifying glass
Magnifying glass
A magnifying glass is a convex lens that is used to produce a magnified image of an object. The lens is usually mounted in a frame with a handle ....
with a transparent base — to examine the tiny prints, still aligned as they are on the negative strips. Negatives themselves can be examined with a loupe, but blacks and whites are the reverse of what is seen through the view finder (hence: a negative), which makes it slightly more difficult to interpret the images. Contact sheets can easily be stored in files in the dark, along with the negatives. A stack of conventional prints is much thicker.
See also
- EnlargerEnlargerAn enlarger is a specialized transparency projector used to produce photographic prints from film or glass negatives using the gelatin silver process, or from transparencies.-Construction:...
for another method of producing prints from negatives - ProjectorProjectorProjector may refer to:*Image projector, a device that projects an image on a surface** Video projector, a device that projects a video signal from computer, home theater system etc.** Movie projector, a device that projects moving pictures from a filmstrip...
for a directory of projector types - Paper negativePaper negativeThe paper negative process consists of using a negative printed on paper to create the final print of a photograph, as opposed to using a modern negative on a film base of cellulose acetate...
- ThumbnailThumbnailThumbnails are reduced-size versions of pictures, used to help in recognizing and organizing them, serving the same role for images as a normal text index does for words...
a digital cognate of the contact print - DarkroomDarkroomA darkroom is a room that can be made completely dark to allow the processing of light sensitive photographic materials, including photographic film and photographic paper. Darkrooms have been created and used since the inception of photography in the early 19th century...
for further reference about printing