Whiteness

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In colorimetry, white is the degree to which the surface is white. Examples of its use may be quantitatively comparing two sheets of white-looking paper viewed individually, but not when aligned.

The International Commission on Information explains it in the following terms:

To promote the uniformity of practice in the evaluation of surface white color, it is recommended that formulÃÆ'Â| for white, W ₂ or W ₁₀ , and for tint, T _{w, 2} or T _{w, 10} , given below, is used for the white comparison of the samples evaluated for the C65 illuminant D65 standard. The application of the formula is limited to commercially-called "white" samples, which do not differ much in color and fluorescence, and they are measured on the same instrument at about the same time. Within this limitation, the formulÃÆ'Â| provides a relative, but not absolute, evaluation of whiteness, which is adequate for commercial use, when measuring tools have appropriate modern and commercial facilities.

Video Whiteness

Calculation

${\ displaystyle W_ {2} = Y_ {2} 800 (x_ {n, 2} -x_ {2}) 1700 (y_ {n, 2} -y_ {2})}  ÂÂ$

${\ displaystyle W_ {10} = Y_ {10} 50800 (x_ {n, 10} -x_ {10}) 1700 (y_ {n, 10} -y_ { 10})}  ÂÂ$

${\ displaystyle T_ {w, 2} = 1000 (x_ {n, 2} -x_ {2}) - 650 (y_ {n, 2} -y_ {2} )}  ÂÂ$

${\ displaystyle T_ {w, 10} = 900 (x_ {n, 10} -x_ {10}) - 650 (y_ {n, 10} -y_ {10} )}  ÂÂ$

Where

• Y is the Y tristimulus value (relative luminance),
• (x, y) is the chromaticity coordinate in the CIE 1931 color space
• (x _n , y _n ) is the chromaticity coordinates of the perfect diffuser (white reference)

The numbers in the subscript indicate the observer: two for the CIE 1931 standard observers and ten for the CIE 1964 standard observers.

Note

• W decreases with white, reaches 0 for a perfect diffuser.
• The color is blue for positive T and yellow for negative T
• The same difference in W can look different.

Maps Whiteness

See also

• Color temperature

src: i.ytimg.com

References

• Schanda, JÃÆ'¡nos (2007). "Chapter 3: CIE Colorimetry". Colorimetry: Understanding the CIE System . Wiley Interscience. pp.Ã, 68-70. ISBN 978-0-470-04904-4. Ã,

src: www.amherst.edu

External links

• ISO 105-J02: Textile 1997 - Testing for color fastness - Part J02: Instrumental assessment of white relative
• ISO 11475: 2004 Paper and board - Determination of white CIE, D65/10 degrees (outdoor sunlight)
• ISO 11476: 2000 Paper and board - Determination of CIE-white, C/2 degree (indoor lighting conditions)
• ISO/AWI 11476 Paper and board - Determination of CIE-white, C/2 degree (indoor lighting conditions)
• Konica Minolta Sensing: White Color
• TAPPI - why the CIE 1931 color space does not work for white paper: COMPARATIVE STUDY OF BRIGHTNESS/WEAKNESS USING ANALYTICAL VARIOUS METHOD IN PAPERED COATS CONTAINED KOAMAN Aksoy, Joyce, Fleming, Department of Paper, and Printing Science and Engineering, West Michigan University

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