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26-446: Kodak Ektar is a professional color negative film introduced in 2008, designed for nature, outdoors, fashion, and product photography. The film offers ultra-fine grains, ultra-vivid colors, and high saturation, and is available in ISO 100 only. Another film named "Ektar" was introduced in 1989 by Eastman Kodak as a semi-professional color negative film, but it was later discontinued and

52-417: 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. 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. Transparent positive prints can be made by printing a negative onto special positive film , as

78-524: A film scanner . Negative film 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. 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 . In

104-495: 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. 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

130-446: 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

156-455: A positive image will usually trigger a negative afterimage quickly via the adaptation process. To experience this phenomenon, one can look at a bright source of light and then look away to a dark area, such as by closing the eyes. At first one should see a fading positive afterimage, likely followed by a negative afterimage that may last for much longer. It is also possible to see afterimages of random objects that are not bright, only these last for

182-412: 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. Film for cameras that use

208-489: A split second and go unnoticed by most people. An afterimage in general is an optical illusion that refers to an image continuing to appear after exposure to the original image has ceased. Prolonged viewing of the colored patch induces an afterimage of the complementary color (for example, yellow color induces a bluish afterimage). The "afterimage on empty shape" effect is related to a class of effects referred to as contrast effects . In this effect, an empty (white) shape

234-444: 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 , 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

260-460: 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. 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. A positive image

286-478: Is greater than zero degrees but less than 180 degrees. Afterimage The remainder of this article refers to physiological afterimages . A common physiological afterimage is the dim area that seems to float before one's eyes after briefly looking into a light source, such as a camera flash. Palinopsia is a common symptom of visual snow . Negative afterimages are generated in the retina but may be modified like other retinal signals by neural adaptation of

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312-426: Is magenta (an equal mixture of red and blue). Positive afterimages, by contrast, appear the same color as the original image. They are often very brief, lasting less than half a second. The cause of positive afterimages is not well known, but possibly reflects persisting activity in the brain when the retinal photoreceptor cells continue to send neural impulses to the occipital lobe . A stimulus which elicits

338-434: Is that there are four opponent channels: red versus cyan, green vs magenta, blue versus yellow, and black versus white. Responses to one color of an opponent channel are antagonistic to those of the other color. Therefore, a green image will produce a magenta afterimage. The green color adapts the green channel, so they produce a weaker signal. Anything resulting in less green is interpreted as its paired primary color, which

364-410: 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 ,

390-407: 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 in so far as the hue can be altered by plus or minus some number of degrees which

416-408: The retinal ganglion cells that carry signals from the retina of the eye to the rest of the brain. Normally, any image is moved over the retina by small eye movements known as microsaccades before much adaptation can occur. However, if the image is very intense and brief, or if the image is large, or if the eye remains very steady, these small movements cannot keep the image on unadapted parts of

442-493: The afterimage because localized areas of vision are still being processed by the brain using adaptations that are no longer needed. The Young-Helmholtz trichromatic theory of color vision postulated that there were three types of photoreceptors in the eye, each sensitive to a particular range of visible light: short-wavelength cones, medium-wavelength cones, and long-wavelength cones. Trichromatic theory, however, cannot explain all afterimage phenomena. Specifically, afterimages are

468-401: 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

494-420: 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. Negatives are normally used to make positive prints on photographic paper by projecting the negative onto the paper with a photographic enlarger or making

520-583: The common C-41 process . It was designed to offer ultra-fine grain. It was manufactured in 25, 100 (replaced the poor selling 125 in June 1991 ), and 1000 ISO formats. 400 speed film was available until 1997. Poor market segmentation was cited as a factor in Kodak's decision to discontinue Ektar in 1994. The film was replaced by the Royal Gold line. The 120 version of Ektar was discontinued in 1997. A new film

546-516: The complementary hue of the adapting stimulus, and trichromatic theory fails to account for this fact. The failure of trichromatic theory to account for afterimages indicates the need for an opponent-process theory such as that articulated by Ewald Hering (1878) and further developed by Hurvich and Jameson (1957). The opponent process theory states that the human visual system interprets color information by processing signals from cones and rods in an antagonistic manner. The opponent color theory

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572-557: 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. Such negative images, however, can have less permanence and less accuracy in reproduction than their digital counterparts. A negative image can allow

598-449: The retina. Afterimages can be seen when moving from a bright environment to a dim one, like walking indoors on a bright snowy day. They are accompanied by neural adaptation in the occipital lobe of the brain that function similar to color balance adjustments in photography. These adaptations attempt to keep vision consistent in dynamic lighting. Viewing a uniform background while adaptation is still occurring will allow an individual to see

624-400: 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

650-456: Was introduced in September 2008 under the name Kodak EKTAR 100, which claims to be the finest-grain color negative film with high saturation and vivid colors available on the market. The film was initially only offered in 35mm, but later the film offering was expanded to include 120 size film, then 4x5 and 8x10 sheet sizes in 2010. Ektar 100 is designed to be very suitable for digitizing using

676-536: Was replaced by Royal Gold. Prior to its use on films, the Ektar name originally referred to Eastman Kodak's premium-priced lenses for professional use, which were introduced in 1936 and sold until the 1960s. In contrast to the branding from other lens-makers, Kodak emphasized that the name was a quality mark rather than referring to any particular optical formula. Ektar started as a color 35mm and 120 semi-professional film introduced by Eastman Kodak in 1989, which used

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