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Color Communication in the Digital Age The Language of ... Color Communicati… · Slide 1 Color...
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Slide 1 Color Communication in the Digital Age The Language of Color Presented by: Brian Ashe Technical Consultant GDSC X-Rite
Transcript of Color Communication in the Digital Age The Language of ... Color Communicati… · Slide 1 Color...
Slide 1
Color Communication in the Digital Age
The Language of Color
Presented by:Brian Ashe
Technical Consultant GDSCX-Rite
Slide 2
Color Communications
– What is color?
– Understand our limitations.
– How can we measure color?
– When is color “good enough”?
– What is the cost of good color?
Objectives
Slide 3
Identify This Color
Slide 4
Identify This Color
Slide 5
b
e
a
d
g
f
h
i
j
k
l
cm
n
o
p
q
rs
t
u
v
w
x
y
z
Which Color Is It?
Slide 6
b
e
a
d
g
f
h
i
j
k
l
cm
n
o
p
q
rs
t
u
v
w
x
y
z
c
Which Color Is It?
Slide 7
• Add density
• Increase detail
• Increase saturation
• Increase sharpness
• Needs more depth
• Add contrast
• Add density
• Balance the neutrals
• Make it “Pop”
• Chalky
• Grainy
• Make colors cleaner
• Match attached copy
• Needs warmth
• Reduce blue 2%
• Needs redder reds
• Colors are too strong
• It feels blown-out
• Does not have shine of transparency
• Just a ‘smidge / tad less’…
• Tone it down
• Too dull / too flat
• Too muddy
• Whiter whites but hold detail
• Fleshier flesh tones
• Give me more shape
• Needs to be commercially acceptable color
• Hold highlight
Ineffective Communication
Slide 8
Count the Dots
Slide 9
x
Afterimages
Slide 10
x
Afterimages
Slide 11
Retinal fatigue
– Brief exposure to strong colors leaves an after image
– Considerable rest may be needed to let the eye recover
The “I” Factor
Slide 12
Simultaneous Contrast
Slide 13
Simultaneous Contrast Experiment
Slide 16
Retinal fatigue
Background effects
– The fovea sees the greatest detail, but is still affected by the
rest of the eye
– Always be aware of your field of view
The “I” Factor
Slide 19
Retinal Fatigue
Background effects
Poor Color Memory
– Two objects must be viewed simultaneously in order to fully
judge their differences
The “I” Factor
Slide 20
6 2
Color Deficiency
Slide 21
Retinal Fatigue
Background effects
Poor Color Memory
Color Deficiency
– 1 in every 13 males suffers from red-green
colorblindness: 1 in every 300 females.
The “I” Factor
Slide 22
The Visible SpectrumLight is Color
Slide 23
Illuminant D65 – Daylight ~ 6500 K
Slide 24
Daylight Spectral Power Distribution Curves
Slide 25
Illuminant A – Incandescent ~ 2856 K
Slide 26
Illuminant F2 - Cool White Fluorescent ~ 4100 K
Slide 27
Daylight D75 Illuminant A
Cool White Fluorescent Horizon
Common Light Sources
Slide 28
Retinal Fatigue
Background effects
Poor Color Memory
Color Deficiency
Lighting conditions
– Failure to adopt standardized viewing conditions
often results in poor color decisions
The “I” Factor
Slide 29
A Incandescent
C Sunlight
D50 Daylight ( Horizon Sky Daylight )
D65 Daylight ( Average North Sky Daylight )
D75 Daylight ( North Sky Daylight – Sky Only )
F2 Cool White Fluorescent
F7 Broad Band White Fluorescent
F11 TL84
F12 Ultralume 3000
Some Standard Illuminants
Slide 30
– Our Eyes can be fooled
– Perceived Color may be Systematically Organized by:
– Hue (color family), Value (or lightness), and Chroma (strength)
– Color is Light: Light is Energy
– Light Sources distribute energy differently
– Perceived Color requires Light, Object, and Observer
– We must Control the Light to Manage our Perception of Color
– Our Eyes have Three Color Channels - - Red, Green, and Blue
What Have we Learned so Far?
Slide 31
Tristimulus Values – XYZ
Slide 32
David MacAdam’s Perception Ellipsoids
Slide 33
It seems that three numbers are required to
define a color in “color space”
Treat these numbers as if you were trying to find an address in an unfamiliar city.
Color Mapping
Slide 34
L*L*+b*+b*
--b*b*
+a*+a*--a*a*
L*L*+b*+b*
--b*b*
+a*+a*--a*a*
The CIE L*a*b* (1976)
Slide 35
L*L* == 42.6542.65a*a* == --23.0123.01b*b* == 10.5010.50
L*L* == 42.6542.65a*a* == --23.0123.01b*b* == 10.5010.50
L*L* == 42.6542.65a*a* == --23.0123.01b*b* == 10.5010.50
Tolerancing in L*a*b*
First a point is measured
Slide 36
Tolerancing in L*a*b*
DL* = ±1.00Da* = ±1.00Db* = ±1.00
DL* = ±1.00Da* = ±1.00Db* = ±1.00
Next limits are set
Slide 37
DE* = DL*2 + Da*2 + Db*2
Tolerancing in L*a*b*
Slide 38
Delta L*a*b* vs. Ellipses
Slide 39
Catch 22
Slide 40
Lightness
Chroma
Hue
What About L*C*h°?
Slide 41
L*C*h° is directly related to L*a*b*
They both plot on the same map
*Remember: Munsell described Hue, Lightness, and Chroma as ‘natural’ mechanisms by which we distinguish shade!
L* = L*C* = a*2 + b*2
h° = Arc Tangent (b* / a*)
Rethink L*C*h°!
Slide 42
C* h°h°
+a-a
+b
-b
+L
-L
How Does L*C*h° Fit?
90°
0°180°
270°
Chroma = Distance from gray
Hue = Angle from Red
Slide 43
L*L* == 42.6542.65C*C* == --23.0123.01h°h° == 155.47155.47
L*L* == 42.6542.65C*C* == --23.0123.01h°h° == 155.47155.47
L*L* == 42.6542.65C*C* == 25.2925.29h°h° == 175.47175.47
Tolerancing in L*C*h°
First a point is measured
Slide 44
Tolerancing in L*C*h°
DL* = ±1.00DC* = ±1.00DH* = ±1.00
DL* = ±1.00DC* = ±1.00DH* = ±1.00
Next limits are specified
Slide 45
While both L*a*b* and L*C*H* tolerance solids seem to
have similar shapes... the L*C*H* solid is free to rotate
about the center of color space.
Appearances Can Be Deceiving
Slide 46
Delta L*C*H* vs. Ellipses
Slide 47
Which would you choose?
Tolerancing: L*a*b* vs. L*C*h°
Delta L*a*b* vs. Ellipses
Delta L*C*H* vs. Ellipses
Slide 48
The CMC2:1 (Color Measurement Committee) calculation
dynamically scales and rotates tolerance ellipsoids in a manner
consistent with human perception.
Automatic Ellipsoids
Slide 49
CMC Tolerancing
Slide 50
L*a*b* CIE 1976 75%
L*C*H* CIE 1976 85%
CMC2:1 CMC, 1988 95%
Color Tolerancing - To Compare…
Slide 51
Modern Instrumentation
What to choose. When to use which and why?
Instrument Geometries – 0º/45º, Sphere, Multi-angle
Colorimeters vs. Spectrophotometers
Transmission vs. Reflection
Slide 52
Is a three-filter, tri-stimulus device
lamp
aperture
filtersreceiver
lampoptics
Colorimeter
Slide 53
How it views the spectrum
Colorimeter
Slide 54
lamp
aperture
filters
receiver
lampoptics
Spectrophotometer
Slide 55
Spectrophotometer – The Spectrum
Slide 56
Provides the “fingerprint” of the color
Gives all of the information of a colorimeter
and more…
– Required for formulation
– Identifies metamerism
– Best QA tool
Color Control - Spectrophotometry
Slide 57
Instrument Geometry – Why use What?
What to choose. When to use which and why?
Instrument Geometries – 0º/45º, Sphere, Multi-angle
Colorimeters vs. Spectrophotometers
Transmission vs. Reflection
Slide 58
Single angle (45°/0°)
lamp
receiver
lamp
Instrument Geometries - 0º/45º
Slide 59
Sphere (D8°)
lamp
Sampleviewing port
Specular port
8°8°
baffle
Instrument Geometries - Spherical
Slide 60
Multi-angle (15°/25°/45°/75°/110°)
lamp
75°
110°
45°25°
15°
Specularangle
Instrument Geometries – Multi-angle
Slide 61
Reflection from Surface (gloss)
Air
Resin
Reflection from Metal Flake
Aluminium FlakePigment Particle
Metallic Additives
Slide 62
Primary Types of Light Distribution
Slide 63
Gloss
Slide 64
Preparation, Presentation, Preservation
Be Consistent Manage variables
Train carefully
Keep things clean
Communicate
Draft clear procedures
Anticipate
Slide 65
Thank youPRESENTED BY
Brian AsheTechnical Consultant GDSC
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