Design of visual environment

Transcription

1 esign of visual environment 6-1

2 Outline CIE Colorimetry for light sources Fundamentals of Colorimetry Planckian radiators or incandescent light sources Correlated color temperature Color rendering index aylight simulation iscussion Supplementary reading and learning: Psychological factors of color in decoration, advertising, computer graphics, digital cinema, videogames and virtual reality Mandatory activity no

3 Basic: Bibliography & Links SMITH, N.A.: Lighting for Health and Safety. Oxford: Butterworth-Heinemann, LILLO JOVER, J.: Ergonomía. Evaluación y diseño del entorno visual. Madrid: Alianza Editorial, Psicología y Educación, BOYCE, P.R.: Human factors in lighting, 2nd ed., London: Taylor & Francis, KOPACZ, J.: Color in Three-imensional esign. New York: McGraw-Hill,

4 Basic: Bibliography & Links CHIAZZARI, S.: The complete book of colour : using colour for lifestyle, health and well-being. London: Element, GARCÍA-GAITE, G.: Iluminación y seguridad laboral. Madrid: Fundación Mapfre, JACKSON, R., MACONAL, L., FREEMAN, K.: Computer generated colour: a practical guide to presentation and display. Chichester: John Wiley and Sons, CIE International Commission on Illumination: ivisions 2, 3 and

5 Bibliography & Links Complementary: ilaura,., HOUSER, K,, MISTRICK, R & STEFFY, G.: The Lighting Handbook, 10 th ed., New York: Illuminating Engineering Society (IES), GAGE, J.: Colour and meaning: art, science and symbolism. London: Thames and Hudson, HELLER, E.: Psicología del color: cómo actúan los colores sobre los sentimientos y la razón. Barcelona: Gustavo Gili, CUTTLE, C.: Lighting by design. 2 nd ed. Oxford: Architectural Press, Elsevier,

6 Bibliography & Links Complementary: Comité Español de Iluminación: Journal of Light & Visual Environment: Light & Engineering: lightandengineering_founders.html. The Lighting Journal: Lighting Research & Technology: 6-6

7 Can we artificially light like (solar) daylight? Introduction: objectives aylight is highly variable average What would be the visual consequences if this is not possible? When is advisable to choose lamps that simulate daylight? 6-7

8 Fundamentals of Colorimetry Color space CIE-1931 XYZ (I): Tristimulus values (area) 6-8

9 Fundamentals of Colorimetry Color space CIE-1931 XYZ (II): X k Y k Z k k 780nm 380nm 780nm 380nm 780nm 380nm 780nm 380nm S S S S x y z 100 y y x 6-9

10 6-10 Lesson 6 Color space CIE-LabC ab h ab (I): Fundamentals of Colorimetry n n n n n Z Z Y Y b Y Y X X a Y Y L 2 2 arctan a b h b a C ab ab

11 Fundamentals of Colorimetry Color space CIE-LabC ab h ab (II): E E H ab ab ab L a b 2 2 L C H C ab, std C ab ab, s sample standard 2 ab h sin 2 2 ab +b +L -a std +a -C std +C -b -L 6-11

12 6-12 Lesson 6 Blackbody radiation (Planck) law: Incandescent light sources Planckian radiators K m c m W c m W 1 T c exp 1 c S P Color temperature

13 Incandescent light sources: Planckian radiators Color temperature (T) Wien law: MAX T mk Boltzmann law: M e T 4 W m -2 Psychological appearance: Warm: T < 3300 K Neutral: T < 5300 K Cool: T > 5300 K 6-13

14 Correlated color temperature Correlated color temperature (T c ) : What happens when the lamp spectrum is unlike any Planckian or incandescent radiator? How indicate that one lamp is color like that of a Planckian radiator? Fluorescent lamp: daylight white Warm white LE XYZ? T c? 6-14

15 Correlated color temperature Historical example (1964): daylight phases S S a S a S a x x y y a x x y y 6-15

16 Correlated color temperature Historical example (1964): daylight phases if T x y C if T x y 4000, T 3.000x C 3.000x c 7000, T 2 K T 2.870x 9 3 c K 2.870x 6 2 c T c T c T c

17 Correlated color temperature Historical example (1964): daylight phases Locus locus P Temperature isoline 6-17

18 Correlated color temperature Quick and current algorithm for many cases: Spectrum S() Coordenates x, y n x y x y e e T C n n A0 A1 exp A2 exp A3 exp t1 t2 n t 3 x e y e A 0 A 1 t 1 A 2 t 2 A 3 t

19 Color rendering index What is the effect that one lamp has on color appearance of materials compared to a reference light source? Normative CIE E test = 1000 lx E ref = 1000 lx X Y Z ref test () () X Y Z ref Test lamp Ref. lamp 6-19

20 Color rendering index Special indexes R i General indexes R a (the first 8) and R b (14) Human skin Olive green 6-20

21 Color rendering index Spectrum S test () Color Temperature T c Type P: < 5000 K Reference lamp S ref () Type : > 5000 K Chromatic adaptation T ref-test 6-21

22 Color rendering index Objects: i = 1,..., 14 [X i, Y i, Z i ] test [X i, Y i, Z i ] ref T ref-test [X i, Y i, Z i ] ref-test E i (CIE ) R i = E i R a, R b 6-22

23 Color rendering index Class Range R a Color appearance Preferred use Acceptable use 1A [90, 100[ Warm Neutral Cool Color assessments, clinical probes, art galleries, museums 1B [80, 90[ Warm Neutral Neutral Cool Home, hotels, restaurants, shops, offices, schools, hospitals Graphic Arts, textile and paper industries, industrial work 2 [60, 80[ Warm Neutral Cool Industrial work Offices, schools 3 [40, 60[ Industries handling big objects Industrial work 4 [20, 40[ 6-23

24 Lightness L coordenate b Lesson 6 Graphic example: high-pressure Na vs. wle lamps Color rendering index Material test composed by 10 samples (CIE 1999, CIELAB) 7.0 Relative values Reference lamp: P27 Reference lamp: P Na Wavelength, nm chroma C ab coordenate a X Y Z T c (K) R a R b R96 Na

25 Lightness L coordenate b Lesson 6 Graphic example: high-pressure Na vs. wle lamps Color rendering index Material test composed by 10 samples (CIE 1999 revision) 1.5E-03 Relative values Reference lamp: 65 Reference lamp: 65 wle E E E Wavelength, nm Chroma C ab coordenate a X Y Z T c (K) R a R b R96 wle

26 Color rendering index Visual comfort zone by Kruithof (1941): Whitish-yellowish light (warm) low light Bluish-whitish light (cool) intense light Revision in 2009 for white LEs by Viénot, urand and Mahler Lamp technical label 6-26

27 5 metamer pairs (65) Lesson 6 Quality factor for lamps trying to simulate the attributes of the solar daylight (65): CIE aylight simulation Visible spectral component (VIS) E 1 (Lab) E 2 (Lab) E 3 (Lab) E 4 (Lab) MI VIS i 1 E i E 5 (Lab) 6-27

28 3 metamer pairs (65) Lesson 6 Quality factor for lamps trying to simulate the attributes of the solar daylight (65): CIE aylight simulation Ultraviolet spectral component (UV) 1 b 1 E 1 (Lab) 2 b 2 3 b 3 E 2 (Lab) E 3 (Lab) MI UV i 1 E i Non fluorescent fluorescent 6-28

29 aylight simulation Final evaluation: combination of two letters E (Lab) = [0, 0.25[ [0.25, 0.50[ [0.50, 1[ [1, 2 [ [2, +[ Category A B C E Graphic example: Xe vs. Metal-Halide lamps Relative values Xe Relative values M-H wavelength, nm wavelength, nm 6-29

30 Reflectance factor Radiance factor Lesson 6 aylight simulation Graphic example: Xe vs. Metal-Halide lamps X 10 Y 10 Z 10 T c (K) MI VIS MI UV Balance A A AA Xe B E BE M-H Metamer Std Xe 1 Metamer Std Wavelength, nm Wavelength, nm 6-30

31 Supplementary reading and learning Read the supplementary lesson no. 6 downloaded from Virtual Campus about color psychology applied to decoration and advertising Compare with this book about lighting & color design for hospitals Resemblances? ifferences? Implementations for digital culture? 6-31

32 Proposed activity nº 3 Relative Weight: 2.5 % elivery process by Virtual Campus evaluation Individual Task: ownload the numerical exercises sheet no. 3 Read, solve the exercise no. 5 Use tutoring tool in case of doubts Submit it using practice delivery tool by Virtual Campus. eadline: 15 th November 6-32