Negative (photography)

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Color positive picture (A) and negative (B), monochrome positive picture (C) and negative (D) Pozytyw i negatyw.jpg
Color positive picture (A) and negative (B), monochrome positive picture (C) and negative (D)

In photography, a negative is an image, usually on a strip or sheet of transparent plastic film, in which the lightest areas of the photographed subject appear darkest and the darkest areas appear lightest. [1] This reversed order occurs because the extremely light-sensitive chemicals a camera film must use to capture an image quickly enough for ordinary picture-taking are darkened, rather than bleached, by exposure to light and subsequent photographic processing.

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In the case of color negatives, the colors are also reversed into their respective complementary colors. Typical color negatives have an overall dull orange tint due to an automatic color-masking feature that ultimately results in improved color reproduction. [2]

Negatives are normally used to make positive prints on photographic paper by projecting the negative onto the paper with a photographic enlarger or making a contact print. The paper is also darkened in proportion to its exposure to light, so a second reversal results which restores light and dark to their normal order. [3]

Negatives were once commonly made on a thin sheet of glass rather than a plastic film, and some of the earliest negatives were made on paper. [4]

Transparent positive prints can be made by printing a negative onto special positive film, as is done to make traditional motion picture film prints for use in theaters. Some films used in cameras are designed to be developed by reversal processing, which produces the final positive, instead of a negative, on the original film. [5] Positives on film or glass are known as transparencies or diapositives, and if mounted in small frames designed for use in a slide projector or magnifying viewer they are commonly called slides.

Negative image

Picture showing a dust storm during the Dust Bowl period, Texas Panhandle, TX Dust bowl, Texas Panhandle, TX fsa.8b27276 edit.jpg
Picture showing a dust storm during the Dust Bowl period, Texas Panhandle, TX
A negative of the previous image. Curiously, it appears to be the original photo. Dust bowl, Texas Panhandle, TX fsa.8b27276 negative.jpg
A negative of the previous image. Curiously, it appears to be the original photo.
Positive colorNegative color

A positive image is a normal image. A negative image is a total inversion, in which light areas appear dark and vice versa. A negative color image is additionally color-reversed, [6] with red areas appearing cyan, greens appearing magenta, and blues appearing yellow, and vice versa.

Under a phenomenon known as the ‘negative picture illusion’, a negative image can be briefly experienced by the human visual system where an afterimage persists subsequent to a prolonged gaze.

Film negatives usually have less contrast, but a wider dynamic range, than the final printed positive images. The contrast typically increases when they are printed onto photographic paper. When negative film images are brought into the digital realm, their contrast may be adjusted at the time of scanning or, more usually, during subsequent post-processing. [7]

Negative film

A strip of four color negatives on 35 mm film that show some images of what looks like a fire hydrant, street lights etc. Filmstrip.jpg
A strip of four color negatives on 35 mm film that show some images of what looks like a fire hydrant, street lights etc.

Film for cameras that use the 35 mm still format is sold as a long strip of emulsion-coated and perforated plastic spooled in a light-tight cassette. Before each exposure, a mechanism inside the camera is used to pull an unexposed area of the strip out of the cassette and into position behind the camera lens. When all exposures have been made the strip is rewound into the cassette. After the film is chemically developed, the strip shows a series of small negative images. It is usually then cut into sections for easier handling. Medium format cameras use 120 film, which yields a strip of negatives 60 mm wide, and large format cameras capture each image on a single sheet of film which may be as large as 20 x 25 cm (8 x 10 inches) or even larger. Each of these photographed images may be referred to as a negative and an entire strip or set of images may be collectively referred to as "the negatives". They are the master images, from which all positive prints will derive, so they are handled and stored with special care.

Many photographic processes create negative images: the chemicals involved react when exposed to light, so that during development they produce deposits of microscopic dark silver particles or colored dyes in proportion to the amount of exposure. However, when a negative image is created from a negative image (just like multiplying two negative numbers in mathematics) a positive image results. This makes most chemical-based photography a two-step process, which uses negative film and ordinary processing. Special films and development processes have been devised so that positive images can be created directly on the film; these are called positive, or slide, or (perhaps confusingly) reversal films and reversal processing.

Despite the market's evolution away from film, there is still a desire and market for products which allow fine art photographers to produce negatives from digital images for their use in alternative processes such as cyanotypes, gum bichromate, platinum prints, and many others. [8] Such negative images, however, can have less permanence and less accuracy in reproduction than their digital counterparts. [9]

Negative images and digital processing

Color positive picture (A); color negative, luminance positive (B); color positive, luminance negative (C); and full negative (D). NegativeTypes.jpg
Color positive picture (A); color negative, luminance positive (B); color positive, luminance negative (C); and full negative (D).

A negative image can allow a different perception of an everyday scene perhaps highlighting spatial relationships and details that are less obvious in the positive image. For example, the photographer Andrew Prokos has produced an award-winning series of photographs under the “inverted” banner. [10] The advent of digital image processing has expanded the possibilities. In a physical photograph the colour and luminance can only be inverted in tandem, but digital processing allows each to be inverted separately. If the hue of an image is rotated by 180 degrees, then the colour of the image is inverted but not its luminance. The negative of such an image has the luminance inverted but not the colour. Whereas a physical image can be either ‘inverted’ or ‘not inverted’, a digital image can exhibit a partial degree of colour inversion [11] in so far as the hue can be altered by plus or minus some number of degrees which is greater than zero degrees but less than 180 degrees.

Related Research Articles

<span class="mw-page-title-main">Photography</span> Art and practice of creating images by recording light

Photography is the art, application, and practice of creating images by recording light, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film. It is employed in many fields of science, manufacturing, and business, as well as its more direct uses for art, film and video production, recreational purposes, hobby, and mass communication.

<span class="mw-page-title-main">Photograph</span> Image created by light falling on a light-sensitive surface

A photograph is an image created by light falling on a photosensitive surface, usually photographic film or an electronic image sensor, such as a CCD or a CMOS chip. Most photographs are now created using a smartphone or camera, which uses a lens to focus the scene's visible wavelengths of light into a reproduction of what the human eye would see. The process and practice of creating such images is called photography.

The following list comprises significant milestones in the development of photography technology.

<span class="mw-page-title-main">Exposure (photography)</span> Amount of light captured by a camera

In photography, exposure is the amount of light per unit area reaching a frame of photographic film or the surface of an electronic image sensor. It is determined by shutter speed, lens F-number, and scene luminance. Exposure is measured in units of lux-seconds, and can be computed from exposure value (EV) and scene luminance in a specified region.

<span class="mw-page-title-main">Multi-exposure HDR capture</span> Technique to capture HDR images and videos

In photography and videography, multi-exposure HDR capture is a technique that creates high dynamic range (HDR) images by taking and combining multiple exposures of the same subject matter at different exposures. Combining multiple images in this way results in an image with a greater dynamic range than what would be possible by taking one single image. The technique can also be used to capture video by taking and combining multiple exposures for each frame of the video. The term "HDR" is used frequently to refer to the process of creating HDR images from multiple exposures. Many smartphones have an automated HDR feature that relies on computational imaging techniques to capture and combine multiple exposures.

<span class="mw-page-title-main">Photographic paper</span> Light-sensitive paper used to make photographic prints

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 visible image; with most papers the image density from exposure can be sufficient to not require further development, aside from fixing and clearing, though latent exposure is also usually present. The light-sensitive layer of the paper is called the emulsion. The most common chemistry was based on silver halide but other alternatives have also been used.

<span class="mw-page-title-main">Reversal film</span> Type of photographic film that produces a positive image on a transparent base

In photography, reversal film or slide film is a type of photographic film that produces a positive image on a transparent base. Instead of negatives and prints, reversal film is processed to produce transparencies or diapositives. Reversal film is produced in various sizes, from 35 mm to roll film to 8×10 inch sheet film.

<span class="mw-page-title-main">Darkroom</span> Room which can be made fully dark to allow for development of photographs and film

A darkroom is used to process photographic film, make prints and carry out other associated tasks. It is a room that can be made completely dark to allow the processing of light-sensitive photographic materials, including film and photographic paper. Various equipment is used in the darkroom, including an enlarger, baths containing chemicals, and running water.

<span class="mw-page-title-main">Enlarger</span> Specialized transparency projector

An enlarger is a specialized transparency projector used to produce photographic prints from film or glass negatives, or from transparencies.

<span class="mw-page-title-main">Contact print</span> Photographic image produced directly from film

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 side down, in contact with a piece of photographic paper, light is briefly shone through the negative or paper and then the paper is developed to reveal the final print.

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 a digital image file projected using an enlarger or digital exposure unit such as a LightJet or Minilab printer. Alternatively, the negative or transparency may be placed atop the paper and directly exposed, creating a contact print. Digital photographs are commonly printed on plain paper, for example by a color printer, but this is not considered "photographic printing".

The Zone System is a photographic technique for determining optimal film exposure and development, formulated by Ansel Adams and Fred Archer. Adams described the Zone System as "[...] not an invention of mine; it is a codification of the principles of sensitometry, worked out by Fred Archer and myself at the Art Center School in Los Angeles, around 1939–40."

The science of photography is the use of chemistry and physics in all aspects of photography. This applies to the camera, its lenses, physical operation of the camera, electronic camera internals, and the process of developing film in order to take and develop pictures properly.

<span class="mw-page-title-main">Cross processing</span>

Cross processing is the deliberate processing of photographic film in a chemical solution intended for a different type of film. The effect was discovered independently by many different photographers often by mistake in the days of C-22 and E-4. Color cross processed photographs are often characterized by unnatural colors and high contrast. The results of cross processing differ from case to case, as the results are determined by many factors such as the make and type of the film used, the amount of light exposed onto the film and the chemical used to develop the film. Cross processing has been used in a variety of photographic and cinematographic practices, most notably rising in popularity during the 1990s. Similar effects can also be achieved with digital filter effects.

Exposure compensation is a technique for adjusting the exposure indicated by a photographic exposure meter, in consideration of factors that may cause the indicated exposure to result in a less-than-optimal image. Factors considered may include unusual lighting distribution, variations within a camera system, filters, non-standard processing, or intended underexposure or overexposure. Cinematographers may also apply exposure compensation for changes in shutter angle or film speed, among other factors.

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 composed of three layers of gelatin, each containing an emulsion of silver halide, which is used as a light-sensitive material, and a different dye coupler of subtractive color which together, when developed, form a full-color image.

In the theory of photography, tone reproduction is the mapping of scene luminance and color to print reflectance or display luminance, with the aim of subjectively "properly" reproducing brightness and "brightness differences".

<span class="mw-page-title-main">Analog photography</span> Non-digital photography that uses film or chemical emulsions

Analog photography, also known as film photography, is a term usually applied to photography that uses chemical processes to capture an image, typically on paper, film or a hard plate. These processes were the only methods available to photographers for more than a century prior to the invention of digital photography, which uses electronic sensors to record images to digital media. Analog electronic photography was sometimes used in the late 20th century but soon died out.

<span class="mw-page-title-main">Photographic film</span> Film used by film (analog) cameras

Photographic film is a strip or sheet of transparent film base coated on one side with a gelatin emulsion containing microscopically small light-sensitive silver halide crystals. The sizes and other characteristics of the crystals determine the sensitivity, contrast, and resolution of the film. Film is typically segmented in frames, that give rise to separate photographs.

Positive has multiple meanings in the world of photography. The two main definitions of positive photography include positive space and positive film.

References

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  2. "Orange in Negative Film | Shutha". shutha.org. Archived from the original on 8 September 2023.
  3. "What is a Negative?". Ilford Photo. 28 March 2017. Retrieved 13 August 2023.
  4. "Photos from Negatives: A Snapshot in the History of Photography". Southtree.
  5. Raso, Michael (30 October 2021). "Negative Film vs Reversal (Positive) Film? What's the Difference?". The Film Photography Project.
  6. Padova, Ted; Murdock, Kelly L. (11 February 2008). Adobe Creative Suite 3 Bible. John Wiley & Sons. ISBN   978-0470130674 . Retrieved 2 November 2017.
  7. "How to Scan B&W Negatives: Adjusting Levels". The Aware Writer. 17 December 2009.
  8. "HP Introduces Large Format Photo Negative Application for Fine-art Quality Professional Photo Edition". Bespoke News Archive. 6 July 2010. Retrieved 2 November 2017.
  9. "Negatives | Deterioration and Preservation of Negatives, Autochromes, and Lantern Slides | Articles and Essays | Genthe Collection | Digital Collections | Library of Congress". Library of Congress, Washington, D.C. 20540 USA. Retrieved 7 September 2023.
  10. "IPA 2020 Winner / Inverted / Andrew Prokos Fine Art / Andrew Prokos". photoawards.com. Retrieved 14 August 2023.
  11. Johnson, Terry (11 July 2022). "Colour Inversion in Photoshop". Medium. Retrieved 13 August 2023.