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 file projected using an enlarger or digital exposure unit such as a LightJet printer. Alternatively, the negative or transparency may be placed atop the paper and directly exposed, creating a contact print.

Printing on black-and-white paper

The process consists of four major steps, performed in a photographic darkroom or within an automated photo printing machine. These steps are:

• Exposure of the image onto the sensitized paper using a contact printer or enlarger;

• Processing of the latent image using the following chemical process:

• Development of the exposed image reduces the silver halide 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. ^[1]

Printing on colour paper

In producing colour prints, additional steps are required to form the color pigments from precursors in the different color-sensitive layers of the emulsion.

Printing from a Slide or Transparency

Printing from a slide or transparency is similar to printing from a negative except that additional processing steps are added to form a reversal print.

Initial development of the print results in a negative image. This development is not followed by fixation, but rather the reduced silver of the negative image is chemically removed from the paper. Since the paper has not been fixed, the unreduced silver halide remains in the emulsion. To form the positive image, the paper is then exposed to light, which creates a latent image in the unreduced silver halide coating. This latent image is developed and fixed to form the positive image.

Printing from a Digital image

Digital photography allows, even encourages people to take more photographs. Most of these photos will be viewed on computer monitors, televisions, Digital photo frames, and online Photo sharing sites. Some will be printed at home using Inkjet printers and more specialized Photo printers. For true Photographic prints, image files can be taken to ?1 hour? photo finishing locations which have digital minilabs or uploaded to Online photo finishing sites which then mail you your prints. Some Chain stores combine these services allowing you to upload your pictures and specify which local store you want to pick the prints up at one hour later.

References

See also

• List of photographic processes
• Film developing
• Gelatin-silver process
• Enlarger
• Contact print
• Photographic print toning
• Photographic paper

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