This document discusses how lighting affects color perception and how color is measured. It explains that light is part of the electromagnetic spectrum visible to human eyes. Our eyes receive light and sense color based on the levels of brightness and the colors red, green, and blue. Different light sources like sunlight and fluorescent bulbs have different spectral power distributions that affect the color temperature (CCT) and color rendering index (CRI) of the light. The CRI indicates how accurately objects are rendered under a light source compared to ideal daylight. Fixture design can change a light's performance. Other metrics discussed include the TM-30, color checker, gamut area index, and flicker frequency, which should be above 100Hz to avoid discomfort.

1. Spectrofotocolorimetry - How lighting affects colorimetry
and how it is really measured
Alfredo Blasco Navarro, CEO, LED Y SPA S.L.
Fernando Barrachina Vázquez, Industrial Engineer, AsenseTEK

2. What is Light
Light is the part of Electromagnetic Radiation that human eyes can perceive.

3. How do we receive light and sense color
Light & Color influence mental & physical status of human

4. How does our eyes receive light and color
Black, White ,Gray,
brightness level
Color, R ,G ,B

5. S/P(Scotopic and Photopic)
Ratio

7. Different sunlight
Different fluorescent light
16:00h 17:00h 18:00h

8. Spectrum Power Distribution

9. Different CCT

10. CIE1931 & Color Uniformity

11. Quiz 1：What the CCT of left-
side and right-side

12. They are in the same CCT
,but in different side

13. How does human feel for
different CRI

14. CRI(Ra)/Re/CQS
CRI(Ra)=Average from R1 to R8(de-saturated samples)
Re=Average from R1 to R15
CIE1964
Non-uniform space
CQS=Average from Q1~Q15(higher saturated samples)
CIELAB
More uniform space

15. Which two are the same group?

16. Human can not easily distinguish from
them, so we need smart spectrometer.

17. Fixture Design will change
the Light Performance
MR16 Tungsten MR16 Tungsten
with Reflector
MR16 Tungsten
with Diffuser and
lampshade
CCT：2943K
CRI：97
R9：88
CCT：2981K
CRI：95
R9：77
CCT：2586K
CRI：98
R9：92

18. IES TM-30-15
Original
CRI = 95
Desaturated
CRI = 80
Red-Enhanced
CRI = 80
Rf = 93
Rg = 100
Rf = 78
Rg = 90
Rf = 78
Rg = 110

19. Basic Value of TLCI
The value in the quote means how
much deviation from Plackian curve
“ + ” leans to Red
“–” leans to Green
If the value is over “1”,the light
is bad for photography or film。
3

20. Color Checker
4. Color checker:
Check the color display
on screen for basic 24
different colors
Reference
Object
Up/Down Out/In
4

21. Colorist Advice
5. Colorist Advice ：
The result is for color adjustment
in 12 sectors.
User has to adjust the light or
camera more when the number is
bigger
5

22. Apple Store

23. Swarovski

24. Museum

25. In HK Airport Disney Store

26. MUJI Store

27. A Seminar Event

28. The Design- Natural Light

29. CRI/CQS Diagram

30. GAI(Gamut Area Index)_EES
Ra=95
CCT=5455K

31. Light flicker refers to quick, repeated changes in
light intensity that makes the light flutter and be
unsteady.
Obvious flicker might let human be uncomfortable.
What is Flicker

32. Flicker Frequency is the number of occurrences of a repeating light
per unit time, The unit is Hertz.
According to IEEE research, obvious low flickering might cause some
diseases. In generally, light flicker frequency design will be
recommended higher than 100Hz, even 160Hz.
.
What is Flicker Frequency

33. Alfredo Blasco Navarro, CEO, LED Y SPA S.L.
Fernando Barrachina Vázquez, Industrial Engineer, AsenseTEK