Assoc.Prof. Eng. Michal Vik, Ph.D.: Colorimetry CMY2. Color order systems

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1 Color order systems

2 Color order systems - definitions A system for categorizing colors An arrangement of color perceptions, color stimuli or material color samples according to certain rules A subset of the world of color according to three attributes that constitute the coordinates of the color system A rational plan for ordering and specifying all object colors by a set of material standards

3 WHAT IS COLOR? CIE definition : (perceived) color Attribute of a visual perception consisting of any combination of chromatic and achromatic content. This attribute can be described by chromatic color names such as yellow, orange, brown, red, pink, green, blue, purple, etc., or by achromatic color names such as white, gray, black, etc., and qualified by bright, dim, light, dark, etc., or by combinations of such names..

4 THREE PRIMARY ATTRIBUTES Hue The attribute of color by means of which a color is perceived to be red, yellow, green, blue, purple, etc. Pure white, black, and grays possess no hue. Saturation the attribute of color perception that expresses the degree of departure from the gray of the same lightness. All grays have zero saturation. Commonly used as a synonym for chroma especially in graphic arts Lightness (1) the attribute of color perception by which a non-self-luminous body is judged to reflect more or less light. (2) the attribute by which a perceived color is judged to be equivalent to one of a series of grays ranging from black to white. Alternate term is value..

5 NBS-ISCC system of color description white light gray -ish white light -ish gray very pale pale, light grayish very light light brilliant medium gray -ish gray grayish moderate strong vivid dark gray dark -ish gray dark grayish dark deep black -ish black blackish very dark very deep

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7 Historical survey Johan Tobias Mayer 1756

8 Johann Heinrich Lambert 1772 Mayer idea extension, Correction based on pigments Strength and Lightness Color order system for sellers

9 Philipp Otto Runge (1810)

10 Albert Henry Munsell * 6. January June A Color Notation 1915 The Munsell Atlas of Color 1918 A.H.Munsell Color Company

11 Munsell system development Munsell s first color models used globes (a) as a base for rotary color mixtures, such that the five hues of equal lightness (called value by Munsell) and chroma appeared as a neutral gray when the globe was spun. Later versions used a tree in which value increased from bottom to top, and chroma on every hue branch increased from center to edge (b).

12 Munsell system organization I V C H The goal of the Munsell system is to present an arrangement of a full sample of colors in equal perceptual intervals over the three dimensions of the color space.

13 Munsell system organization II Munsell hue, value and chroma can be varied independently so all colors can be arrange according the the three attributes in a three-dimensional space. The neutral colors are placed along a vertical line, called the neutral axis with black at the bottom, white at the top and all grays in between. The different hues are display-ed at various angles around the neutral axis. The chroma scale is perpendicular to the axis, increasing outward. This three-dimensional arrangement of colors is called the Munsell color space.

14 Munsell definition of HVC Hue Specifically and technically, distinctive quality of coloring in an object or on a surface in which red, yellow, green, blue, etc., that in which colors of equal luminosity and chroma may differ. Value In printing and the allied arts, relation of one object, part, or atmospheric plane of a picture to the others, with reference to light and shade, the idea of hue being abstracted. Chroma The degree of sensation from that of white or gray; the intensity of distinctive hue, color intensity..

15 James Clerk Maxwell Color disk 19th March 1855 Maxwell has had presentation at Royal Society in Edinburgh.

16 Hue Present day system contains 40

17 Value Value numbers are in interval 0-10

18 Chroma Chroma values theoretical interval 0-50.

19 Munsell Notation

20 Present edition of Munsell Book of Color Matte Collection 1270 samples Glossy Collection 1564 samples Nearly Neutrals Collection 1100 samples

21 Munsell color tree and real colors body Munsell color body is limited only on real colors In Munsell color tree are included real and virtual colors

22 Assoc.Prof. Eng. Michal Vik, Ph.D.: Colorimetry CMY2 Chromatics plane of Munsell Book of Colors and its representation on CRT monitor These colors (all croshatched) CRT or LCD monitor is not able to real display

23 Munsell Perceptual Uniformity System was reformulated in 1929 to be more perceptually uniform than before. Recent investigations showed that it still leaves something to be desired. However, the Munsell Color System is still a valuable resource because it has been studied so extensively.

24 Michel Eugène Chevreul ( ) 1839

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27 Karl Ewald Konstantin Hering ( ) 1918) B R A I N Hering: All colors can be described in terms of 4 psychological color primaries R, G, B, and Y.

28 Natural Colour System I Dr Lars Sivik, Prof Gunnar Tonnquist and Dr. Anders Hård, 2004

29 Natural Colour System II

30 Natural Colour System III w: whiteness s: blackness r: redness

31 NCS :sscc-aφφb whiteness blackness yellowness redness blueness greenness A(%) NCS :s = 30 NCS :c = y + r + b + g = = 60 w + s + c = 100 NCS : φ= 100 g/( b + g) = /( 36+24) = 40 NCS : 3060 B40G

32 Natural Colour System versus Munsell Colour Notation

33 Wilhelm Ostwald ( )

34 Ostwald I

35 Ostwald II

36 Pantone I

37 Pantone II Pantone colors body

38 Pantone III

39 Colorcurve

40 RAL