Photographic printing is the process of producing a final image on paper for viewing, using
chemically sensitized paper. The paper is exposed to a photographic
negative, a positive
transparency (or ''slide''), or a
digital image
A digital image is an image composed of picture elements, also known as ''pixels'', each with ''finite'', '' discrete quantities'' of numeric representation for its intensity or gray level that is an output from its two-dimensional functions ...
file projected using an
enlarger
An enlarger is a specialized transparency projector used to produce photographic prints from film or glass negatives, or from transparencies.
Construction
All enlargers consist of a light source, normally an incandescent light bulb shining thou ...
or digital exposure unit such as a
LightJet or
Minilab
A minilab is a small photographic developing and printing system or machine, as opposed to large centralized photo developing labs. Many retail stores use film or digital minilabs to provide on-site photo finishing services.
With the increase in ...
printer. Alternatively, the negative or transparency may be placed atop the paper and directly exposed, creating a
contact print
A contact print is a photographic image produced from film; sometimes from a film negative, and sometimes from a film positive or paper negative. In a darkroom an exposed and developed piece of film or photographic paper is placed emulsion si ...
. Digital photographs are commonly printed on plain paper, for example by a
color printer, but this is not considered "photographic printing".
Following exposure, the paper is
processed to reveal and make permanent the
latent image
{{citations needed, date=November 2015
A latent image is an invisible image produced by the exposure to light of a photosensitive material such as photographic film. When photographic film is developed, the area that was exposed darkens and forms ...
.
Printing on black-and-white paper
The process consists of four major steps, performed in a photographic
darkroom
A darkroom is used to process photographic film, to make prints and to carry out other associated tasks. It is a room that can be made completely dark to allow the processing of the light-sensitive photographic materials, including film and ph ...
or within an automated photo printing machine. These steps are:
*Exposure of the image onto the sensitized paper using a
contact print
A contact print is a photographic image produced from film; sometimes from a film negative, and sometimes from a film positive or paper negative. In a darkroom an exposed and developed piece of film or photographic paper is placed emulsion si ...
er or
enlarger
An enlarger is a specialized transparency projector used to produce photographic prints from film or glass negatives, or from transparencies.
Construction
All enlargers consist of a light source, normally an incandescent light bulb shining thou ...
;
*
Processing of the latent image using the following chemical process:
**Development of the exposed image reduces the
silver halide
A silver halide (or silver salt) is one of the chemical compounds that can form between the element silver (Ag) and one of the halogens. In particular, bromine (Br), chlorine (Cl), iodine (I) and fluorine (F) may each combine with silver to prod ...
in the latent image to metallic silver;
**Stopping development by neutralising, diluting or removing the developing chemicals;
**Fixing the image by dissolving undeveloped silver halide from the light-sensitive emulsion:
**Washing thoroughly to remove processing chemicals protects the finished print from fading and deterioration.
Optionally, after fixing, the print is treated with a ''hypo clearing agent'' to ensure complete removal of the fixer, which would otherwise compromise the long term stability of the image. Prints can be chemically toned or
hand coloured after processing.
Panalure paper
Kodak
The Eastman Kodak Company (referred to simply as Kodak ) is an American public company that produces various products related to its historic basis in analogue photography. The company is headquartered in Rochester, New York, and is incorpor ...
Panalure is a
panchromatic
Panchromatic emulsion is a type of black-and-white photographic emulsion that is sensitive to all wavelengths of visible light.
Description
A panchromatic emulsion renders a realistic reproduction of a scene as it appears to the human eye, altho ...
black-and-white
Black-and-white (B&W or B/W) images combine black and white in a continuous spectrum, producing a range of shades of grey.
Media
The history of various visual media began with black and white, and as technology improved, altered to color. ...
photographic printing paper. Panalure was developed to facilitate the printing of full-tone black-and-white images from colour
negatives – a difficult task with conventional
orthochromatic
In chemistry, orthochromasia is the property of a dye or stain to not change color on binding to a target, as opposed to metachromatic stains, which change color. The word is derived from the Greek '' orthos'' (correct, upright), and chromatic (c ...
papers due to the orange tint of the film base. Panalure also finds application as paper negatives in
large format
Large format refers to any imaging format of or larger. Large format is larger than "medium format", the or size of Hasselblad, Mamiya, Rollei, Kowa, and Pentax cameras (using 120- and 220-roll film), and much larger than the frame o ...
cameras. It is generally not suitable for conventional black-and-white printing, since it must be handled and developed in near-complete darkness.
Kodak has announced that it will no longer produce or sell this product. However, as of early 2006, it is still available from various online retailers.
Silver mirroring
Silver mirroring, or "silvering", is a degradation process of old black-and white-photographic prints caused by conversion of the black
silver oxide
Silver oxide is the chemical compound with the formula Ag2O. It is a fine black or dark brown powder that is used to prepare other silver compounds.
Preparation
Silver oxide can be prepared by combining aqueous solutions of silver nitrate and a ...
to silver metal. This results in a slightly bluish, reflective patch in the darkest part of a print or negative when examined in raking light. It often indicates improper storage of the prints.
[Notch Code (2012): ]
Forms of Photograph Degradation: Silver Mirroring
'. Archives and Special Collections Blog University Libraries, University of South Dakota; dated January 17, 2012. Accessed on 2020-05-05.
Printing on coloured paper
''For more info see also:
Chromogenic print
A chromogenic print, also known as a C-print or C-type print, a silver halide print, or a dye coupler print, is a photographic print made from a color negative, transparency or digital image, and developed using a chromogenic process. They are co ...
''
Colour papers require specific chemical processing in proprietary chemicals. Today's processes are called
RA-4
RA-4 is Kodak's proprietary name for the chemical process most commonly used to make color photographic prints. It is used for both minilab wet silver halide digital printers of the types most common today in photo labs and drug stores, and for pri ...
, which is for printing colour negatives, and
Ilfochrome
Ilfochrome (also commonly known as Cibachrome) is a dye destruction positive-to-positive photographic process used for the reproduction of film transparencies on photographic paper. The prints are made on a dimensionally stable polyester base as o ...
, for colour transparencies.
Printing from colour negatives
*Colour negatives are printed on
RA-4
RA-4 is Kodak's proprietary name for the chemical process most commonly used to make color photographic prints. It is used for both minilab wet silver halide digital printers of the types most common today in photo labs and drug stores, and for pri ...
papers and produce a
Type C print
A chromogenic print, also known as a C-print or C-type print, a silver halide print, or a dye coupler print, is a photographic print made from a color negative, transparency or digital image, and developed using a chromogenic process. They are co ...
. These are essentially the same as
colour negative films in that they consist of three emulsion layers, each sensitive to
red
Red is the color at the long wavelength end of the visible spectrum of light, next to orange and opposite violet. It has a dominant wavelength of approximately 625–740 nanometres. It is a primary color in the RGB color model and a secondar ...
,
green
Green is the color between cyan and yellow on the visible spectrum. It is evoked by light which has a dominant wavelength of roughly 495570 Nanometre, nm. In subtractive color systems, used in painting and color printing, it is created by ...
and
blue
Blue is one of the three primary colours in the RYB colour model (traditional colour theory), as well as in the RGB (additive) colour model. It lies between violet and cyan on the spectrum of visible light. The eye perceives blue when obs ...
light. Upon processing, colour couplers produce
cyan
Cyan () is the color between green and blue on the visible spectrum of light. It is evoked by light with a predominant wavelength between 490 and 520 nm, between the wavelengths of green and blue.
In the subtractive color system, or CMYK color ...
,
magenta
Magenta () is a color that is variously defined as pinkish- purplish-red, reddish-purplish-pink or mauvish-crimson. On color wheels of the RGB (additive) and CMY (subtractive) color models, it is located exactly midway between red and blue. I ...
and
yellow
Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In the R ...
dyes, representing the true colours of the subject. The processing sequence is very similar to the
C-41 process
C-41 is a chromogenic color print film developing process introduced by Kodak in 1972, superseding the C-22 process. C-41, also known as CN-16 by Fuji, CNK-4 by Konica, and AP-70 by AGFA, is the most popular film process in use, with most photofin ...
.
*Rollei make a film called 'Digibase 200 Pro' that is like a conventional C-41 film but it has no orange mask, allowing easy prints on black-and-white paper with a grade 2 or 3 variable contrast filter
Printing from colour transparencies
*Ilfochrome paper uses the
dye destruction Dye destruction or dye bleach is a photographic printing process, in which dyes embedded in the paper are bleached (destroyed) in processing. Because the dyes are fully formed in the paper prior to processing, they may be formulated with few constra ...
process to produce prints from positive transparencies. The colour dyes are incorporated into the paper and bleached during processing.
Ilfochrome,
EP2 and
Type R print papers and chemicals are no longer in production.
References
See also
*
Contact print
A contact print is a photographic image produced from film; sometimes from a film negative, and sometimes from a film positive or paper negative. In a darkroom an exposed and developed piece of film or photographic paper is placed emulsion si ...
*
Film developing
*
Gelatin-silver process
The gelatin silver process is the most commonly used chemical process in black-and-white photography, and is the fundamental chemical process for modern analog color photography. As such, films and printing papers available for analog photography ...
*
List of photographic processes
A list of photographic processing techniques.
Color
*Agfacolor
** Ap-41 process (pre-1978 Agfa color slides; 1978-1983 was a transition period when Agfa slowly changed their color slide films from AP-41 to E6)
*Anthotype
*Autochrome Lumière, 190 ...
*
Photographic paper
Photographic paper is a paper coated with a light-sensitive chemical formula, like photographic film, used for making photographic prints. When photographic paper is exposed to light, it captures a latent image that is then developed to form a v ...
*
Photographic print toning
In photography, toning is a method of altering the color of black-and-white photographs. In analog photography, it is a chemical process carried out on metal salt-based prints, such as silver prints, iron-based prints (cyanotype or Van Dyke b ...
*
Standard photographic print sizes
{{photography subject
Photographic processes
Non-impact printing