41 Reference Colors for the new wide DCI-P3 Color Gamut Standard
Figure 2a
below shows 41 Reference Colors for the
new wide DCI-P3 Color Gamut as White, Gray, and Black circles.
The 10 Black circles on the outer triangle
are the 100% fully Saturated Colors on the periphery.
The 3 inner sets of Gray triangles are the 25%, 50% and 75% Saturated Colors
between the inner White Point and the 100% Saturated Colors on the periphery.
The White circle is the White Point with 0% Color Saturation.
We have accurately calculated the Colors and Reference Colors for each
of the 3 Galaxy S8 Standard Color Gamuts: DCI-P3, sRGB / Rec.709, and Adobe RGB.
The colors in
Figure 2a
have been calculated to show the true colors
within the DCI-P3 Color Gamut - the colors shown in most published
Color Gamuts are wildly incorrect.
For an in-depth discussion and analysis of all the
Standard Color Gamuts see this
article.
Note that in order to see the true DCI-P3 colors in Figure 2a your display must
support the DCI-P3 Color Gamut - if not then you will instead see
the color saturation range that your display can produce,
which in most cases will be lower than DCI-P3.
Figure 2a. 41 Reference Colors for the DCI-P3 Color Gamut Standard
Note that Complementary Colors lie directly across from one another through the White Point.
The 4 sets of triangles are the 25% 50% 75% and 100% Saturated Colors.
Uniform Color Diagrams
All color measurements are plotted on 1976 CIE Uniform Color Diagrams
with (u',v') color coordinates.
Note that the older 1931 CIE Diagrams that are published by many reviewers
with (x,y) color coordinates
are highly non-uniform and are meaningless for Color Accuracy.
Also the still referenced NTSC Color Gamut is from 1953 and has been
obsolete for over 30 years so it is also meaningless for specifying the
current Color Gamuts now in use.
For an in-depth discussion and analysis of Color Gamuts see this
article.
Absolute Color Accuracy Plots
The Galaxy S8 has user selectable Screen Modes.
AMOLED Cinema screen mode:
Figure 2b
below shows the measured on-screen colors for the
DCI-P3 Reference Colors.
Basic screen mode:
Figure 2c
below shows the measured on-screen colors for the
sRGB / Rec.709 Reference Colors.
AMOLED Photo screen mode:
Figure 2d
below shows the measured on-screen colors for the
Adobe RGB Reference Colors.
Reference Colors and Measured Colors
The
Reference Colors
in
Figures 2b-2d
are all shown as Black circles and the Measured
Colors for each of the Screen Modes are shown as Red circles.
Color Errors smaller than the appropriate JNCD are not visually noticeable.
The 1 JNCD and 3 JNCD Errors are discussed next and are shown in the Figures below.
Just Noticeable Color Difference JNCD
The on-screen colors produced by any display can be measured using a
Spectroradiometer together with our proprietary DisplayMate Test Patterns.
The accuracy of the colors can then be calculated using the
1976 CIE Uniform Chromaticity color space and compared to the
eye's sensitivity to color.
We present the color accuracy and errors here in terms of
MPCD Minimum Perceptible Color Difference or
JNCD Just Noticeable Color Difference,
where 1 MPCD = 1 JNCD = Δ(u'v') = 0.0040 on the
CIE 1976 Uniform Chromaticity Scale.
Color differences less than 1 JNCD are visually indistinguishable,
while values greater than 1 JNCD are visually noticeable when the
two colors are touching on-screen.
When the colors are not touching and are further apart,
the visual threshold for Just Noticing a Color Difference is higher.
Here we will use 3 JNCD for the threshold of
a visually noticeable display color difference.
The 3 JNCD color difference is shown in the Figures below.
Any Display Color Error less than 3 JNCD on a display is not visually noticeable and appears perfectly accurate to the eye.
For an in-depth discussion and analysis of Absolute Color Accuracy see this
article.
Figure 2b. AMOLED Cinema Screen Mode Absolute Color Accuracy Plots
The AMOLED Cinema Screen Mode provides an accurate color match to the DCI-P3 Color Gamut.
Figure 2c. Basic Screen Mode Absolute Color Accuracy Plots
The Basic Screen Mode provides an accurate color match to the standard sRGB / Rec.709 Color Gamut.
Figure 2d. AMOLED Photo Screen Mode Absolute Color Accuracy Plots
The AMOLED Photo Screen Mode provides an accurate color match to the Adobe RGB Color Gamut.
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