Display Standard - Veritas et Visus

Veritas et Visus Display Standard February 2009
There is substantial crowding above 40% of maximum signal intensity, but note that on this 1000:1 logarithmic
scale the diameter of the round data points corresponds to a 6% shift in luminance.
Figure 7: Magnified view of Figure 6 near peak luminance and signal intensity
This figure enlarges the portion of Figure 6 at high peak luminance and signal intensity in order to show the
significant differences between the transfer functions on a magnified scale so they are easier to see. Note the
significant convex curvature for the Samsung unit, which begins with a lower gamma of 2.00 between 100 and 80%
signal, and then steepens significantly to 2.38 between 80 and 60% signal. The Sharp unit has the opposite concave
curvature with its gamma shifting downward from 2.33 for 100 to 75% signal to 2.16 between 75 to 50% signal.
Referring back to Figure 6 the Sharp transfer function then steepens significantly between 40 and 25% signal with
a very high gamma of 3.25 before returning back to significant concave below 20% signal. These variations in the
transfer functions affect not only the picture’s gray scale and contrast, but also the resulting hue and saturation for
all color mixtures, because the individual R,G,B intensities simultaneously dip into different portions of the transfer
function.
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