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| [[File:Planckian-locus-in-mireds.png|thumb|Close up of the [[Planckian locus]] in the [[CIE 1960 color space]], with the isotherms in mireds. Note the even spacing of the isotherms when using the reciprocal temperature scale. The even spacing of the isotherms on the locus implies that the mired scale is a better measure of perceptual [[color difference]] than the temperature scale.]]
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| [[File:Planckian-locus.png|thumb|Close up of the Planckian locus in the [[CIE 1960 color space]], with the isotherms in kelvin. The range of isothermal color temperatures, as in the previous diagram, is from 1000 K (1000 MK<sup>-1</sup>) to 10,000 K (100 MK<sup>-1</sup>).]]
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| Contracted from the term '''micro reciprocal degree''', the '''mired''' is a unit of measurement used to express [[color temperature]]. It is given by the formula:
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| :<math>M=\frac{1000000}{T}</math>
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| where ''M'' is the mired value desired, and ''T'' is the color temperature in [[kelvin]]. | |
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| For convenience, ''decamireds'' are sometimes used, with each decamired equaling ten mireds. The [[SI]] unit is the '''reciprocal megakelvin''' (MK<sup>−1</sup>), shortened to ''mirek'', but this term has not gained traction.<ref>{{cite book|title=Colorimetry: Fundamentals and Applications|page=84|first=Noboru|last=Ohta|coauthors=Robertson, Alan R.|isbn=0-470-09472-9|publisher=Wiley|year=2005}}</ref>
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| The use of the term ''mired'' dates back to Irwin G. Priest's observation in 1932 that the [[just noticeable difference]] between two [[illuminant]]s is based on the difference of the [[multiplicative inverse|reciprocals]] of their temperatures, rather than the difference in the temperatures themselves.<ref>{{cite journal|title=A proposed scale for use in specifying the chromaticity of incandescent illuminants and various phases of daylight|first=Irwin G.|last=Priest|journal=[[JOSA]]|date=February 1932|volume=23|issue=2|pages=41–45|url=http://www.opticsinfobase.org/abstract.cfm?URI=josa-23-2-41|format=abstract|doi=10.1364/JOSA.23.000041}}</ref>
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| ==Examples==
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| A blue sky, which has a color temperature ''T'' of about 25,000 K, has a mired value of ''M'' = 40 mireds, while a standard electronic [[photography]] [[flash (photography)|flash]], having a color temperature ''T'' of 5000 K, has a mired value of ''M'' = 200 mireds.
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| In [[photography]], mireds are used to indicate the color temperature shift provided by a [[Photographic filter|filter]] or [[color gel|gel]] for a given [[film]] and light source. For instance, to use a tungsten light (3200 K) in natural light (say, 5700 K) without introducing a [[color cast]], one would need a corrective filter or gel providing a mired shift of
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| <math>\frac{10^6}{5700} - \frac{10^6}{3200} \approx -137\ \mbox{MK}^{-1}</math>
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| This corresponds to a color temperature blue (CTB) filter.<ref>{{cite book| url=http://books.google.com/?id=1JL2jFbNPNAC&pg=PA172&lpg=PA172&dq=ctb+159+mired| title=Cinematography: Theory and Practice : Imagemaking for Cinematographers |first=Blain|last=Brown|isbn=0-240-80500-3|page=172|publisher=Focal Press|year=2002}}</ref>
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| ==References==
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| <references/>
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| [[Category:Units of measurement]]
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| [[Category:Non-SI metric units]]
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| [[Category:Color]]
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| {{film-term-stub}}
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Here is my web page are psychics real (http://Test.Jeka-Nn.ru/)