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light filtering) as a cheap alternative to expensive glass-backed filters. Such filters can be used both over color camera lenses, and to filter visible light from IR illumination sources. Such filter stock is most easily made available most simply by having any commercial color negative film developed after being fully exposed to light. The leaders of 35mm film are ideal for this, without wasting an entire roll of film. (Some special communication may be necessary in such submission, to ensure that all of the "black" negative film thus produced is indeed returned, and that there is no need to print the color-negative results on photographic paper). In the same way, visually opaque "black" color-positive film emulsions mounted in cardboard, as for routine slide projection, provide inexpensive cardboard-mounted infrared filters. Film sizes larger than 35 mm may be handled in the same way for larger filter production.
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Since the dyes in processed film block various part of visible light but are all fairly transparent to infrared, dark black sections of any processed film (where all visible colors are blocked) pass only infrared light and are commonly used (layering one over another if necessary for better visual
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of the photo to a cooler color. Because of this, the term "IR filters" is commonly used to refer to filters that pass infrared light while completely blocking other wavelengths. However, in some applications the term "IR filter" still can be used as a synonym of infrared cut-off filter.
266:. Digital cameras are usually equipped with IR-blocking filters to prevent unnatural-looking images. IR-transmitting (passing) filters, or removal of factory IR-blocking filters, are commonly used in
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to near-infrared light. These filters typically have a blue hue to them as they also sometimes block some of the light from the longer red
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where the name of the filter denotes the wavelengths that are blocked, and in line with the convention for
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light. Such filters appear black to the eye, but are transparent when viewed with an IR sensitive device.
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marginally allows more light in the blue wavelength to pass resulting in a slight shift of the
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sensors) have sensitivities extending into the near-infrared. Such sensors may extend to 1000
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Optical filters that block near-infrared while passing visible light
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206:IR transmitting/passing filters in photography
214:IR transmitting filters, used in photography.
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218:In contrast to the naming convention of
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62:adding citations to reliable sources
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144:Infrared Color Photography
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77:"Infrared cut-off filter"
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292:Infrared Photography,
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160:heat-absorbing filters
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339:Interference filter
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56:Please help
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330:Cold mirror
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250:Unlike the
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200:wavelengths
184:solid state
334:Hot mirror
156:IR filters
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174:(such as
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319:See also
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102:scholar
66:removed
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