1. Announcements 4/9/12 Prayer Roy G. Biv - http://www.youtube.com/watch?v=Gf33ueRXMzQ (2:41)http://www.youtube.com/watch?v=Gf33ueRXMzQ HW 26 due today (but it’s very likely Claira won’t pick it up until Thursday night. Shhh!) Exam 3 – Should be graded/entered by end of today Final Exam: My apologies, can’t take it in the Testing Center. Scheduled exam date/time: Tues Apr 17, 3-6 pm. a. a.Any conflicts? b. b.Start at 2 pm? c. c.Some detailed info on the problems… Foxtrot

2. Reading Quiz Just kidding

3. The Goal

4. Worked Example X = Y = Z = Normalize (because “color” should not depend on overall intensity) x = y = z =

5. xyY

6. Another Worked Example What is (x,y) for a delta function at 560 nm? My estimates: X = 0.59 Y = 0.98 Z = 0 x =.38 y =.62 Do that for every wavelength  the “locus” curve

7. Chromaticity Diagram Things to observe The locus Example: 560 nm  (0.38, 0.62) The white point = (0.33, 0.33) Basic color mixing (blue + green = cyan, etc.) “Line of purples” Linearity: more advanced combining colors Complementary colors (can mix to get white)

8. sRGB “blue” = (0.15, 0.06) “red” = (0.65, 0.33) “green” = (0.30, 0.60) (If xyY is specified, must first transform to XYZ)

9. sRGB “blue” = (0.15, 0.06) “red” = (0.65, 0.33) “green” = (0.30, 0.60) Mixing three sources: triangle “Gamut”

10. On the advantages of monochromatic sources “green” = (0.30, 0.60) “red” = (0.65, 0.33) “blue” = (0.15, 0.06)

11. What’s the Color of Blackbody Radiation? Wikipedia “Color Temperature”  K 5000K 2000K 1000K The Sun

12. Color of the Sun? The Sun “Stop It”

13. For a given (x,y) point Dominant color (hue), D Saturation (purity), P Complement color, C What about this point?

14. Summary: Ways to Specify Color R,G,B (original color matching functions) X,Y,Z x,y,Y hue, saturation, Y (“hue, brightness, saturation”) sRGB R,G,B coordinates (if in sRGB gamut) That’s All, Folks