Experiments on subtractive color mixing with a spectrophotometer

American Journal of Physics

Volumn 75, Issue 4, 2007, Pages 313-319

  Gilbert, P U P A ^a   Haeberli, Willy ^a  

^a University of Wisconsin Madison   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 34147151208     PISSN: 00029505     EISSN: None     Source Type: Journal    
DOI: 10.1119/1.2431654     Document Type: Article

References (20)

1. Definitions: Given any color, a matching color that appears to the normal retina identical to the color in question, can always be obtained by combining light of a single wavelength with white light (except for magentas and purples, which are specified by the complementary wavelength). The wavelength of the matching color is called the dominant wavelength. The corresponding attribute of visual sensation is called the hue. The fraction of white light is called saturation. Saturation is also known as purity. High saturation colors require a small percentage of white in the matching color, low saturation colors require a large percentage of white. These are pale pink, sky blue, pale yellow, beige, and all colors commonly called pastels. The adjectives saturated and pale are therefore antonyms. To match those colors, the matching color requires a large fraction of white. Some authors define saturation in paints and pigments to be the parameter related to the amount of black, but we do not see a reason for such distinction. Brightness (also known as lightness) is the parameter of a color according to which an area appears to emit more or less light. The adjectives bright and dark (or light and dark) are therefore antonyms. In the literature there is a preference to use the term brightness for luminant sources, and lightness for illuminated surfaces. Different color systems (Munsell, Oswald, and DIN) use other terms (for example, value, chroma), but for simplicity we use terminology familiar from everyday English.
2. P. Kubelka and F. Munk, "Ein Beitrag zur Optik der Farbanstriche." Z. Tech. Phys. (Leipzig) 12, 593-601 (1931).
3. Chet S. Haase and Gary W. Meyer, "Modeling pigmented materials for realistic image synthesis," ACM Trans. Graphics 14, 305-335 (1992).
4. The Kubelka-Munk theory is presented in accessible form in Mahnaz Mohammadi and Roy S. Berns, "Verification of the Kubelka-Munk turbid media theory for artist acrylic paint," MCSL technical report summer 2004, 〈www.art-si.org/publications.htm〉.
5. Ocean Optics CHEM2-VIS-FIBER USB2000-VIS-NIR fiber optic spectrometer, 〈oceanoptics.com〉. The price (including a light source and cuvette holder for absorption experiments, which are not used here) is $1499 with trade in. The cost of an Ocean Optics spectrometer with a 650 channel CCD (Red Tide USB650) is $999 (without optical fiber or software) and is available at 〈oceanoptics.com〉, 〈vernier.com〉, and 〈pasco.com〉.
6. The lamp is a W.A.C. lighting model 900P with a built-in transformer. The light bulb is an MR16 20W narrow beam bulb (color temperature 2050 K). Lower wattage bulbs (MR11 or MR8) may be more suitable but did not fit our lamp.
7. Edmund Optics NT45-648, 〈www.edmundoptics.com〉NT45-648.
8. 50 mm × 50 mm additive and subtractive dichroic filters set, NT-46-140 and NT-46-141, Edmund Optics.
9. Color Film Gel Sheets #10026, Rainbow Symphony, 〈store. rainbowsymphonystore.com/cofige.html〉.
10. Winsor & Newton Galeria acrylic paints: process yellow (pigment PY74), process magenta (PV19), and process cyan (PB 15:3).
11. Dahler Rowney acrylic paints: titanium white 009 and chromium red 503.
12. Van Gogh acrylic paints Azo orange 276 and black.
13. Van Gough acrylic paints: blue #504 and red #396.
14. Paints used for these experiments were Van Gogh acrylic paints (ultramarine blue #504 and primary yellow #275).
15. 〈www.cs.bham.ac.uk/~mer/colour/cie.html).
16. Kurt Nassau, The Physics and Chemistry of Color, 2nd ed. (Wiley, New York, 2001), Chap. 1.
17. G. Waldman, Introduction to Light: The Physics of Light, Vision and Color (Dover, Mineola, NY, 2002), Chap. 11.
18. T. N. Cornsweet, Visual Perception (Academic, New York, 1974).
19. A. Byrne and D. Hilbert, Readings on Color: The Science of Color (MIT, Cambridge, MA, 1997).
20. P. U. P. A. Gilbert and W. Haeberli, Physics in the Arts (Elsevier, Amsterdam, 2007).