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

er or

; * 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 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

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 ...

. 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.