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To: gubamyster

I thought WHITE was the absence of color and black is ALL colors combined.


2,506 posted on 11/06/2019 11:35:24 AM PST by Lakeside Granny ( God's Word says, "Before I formed you in the womb I knew you..." Jeremiah 1:5))
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To: Lakeside Granny
"I thought WHITE was the absence of color and black is ALL colors combined."

It is. That is why I erased it from the comment I made. It is funny that gub and I thought exactly the same though.

So NOW everyone that isn't white calls themselves people of color?

2,510 posted on 11/06/2019 11:43:18 AM PST by Spunky ("Immigration is a privilege, not a right." President Donald Trump)
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To: Lakeside Granny

White objects
Color vision allows us to distinguish different objects by their color. In order to do so, color constancy can keep the perceived color of an object relatively unchanged when the illumination changes among various broad (whitish) spectral distributions of light.[28]

The same principle is used in photography and cinematography where the choice of white point determines a transformation of all other color stimuli. Changes in or manipulation of the white point can be used to explain some optical illusions such as The dress.

While there is no single, unique specification of “white light”, there is indeed a unique specification of “white object”, or, more specifically, “white surface”. A perfectly white surface diffusely reflects (scatters) all visible light that strikes it, without absorbing any, irrespective of the light’s wavelength or spectral distribution.[29][30] Since it does not absorb any of the incident light, white is the lightest possible color. If the reflection is not diffuse but rather specular, this describes a mirror rather than a white surface.[31][29]

Reflection of 100% of incident light at all wavelengths is a form of uniform reflectance, so white is an achromatic color, meaning a color without hue.[32][33] The color stimulus produced by the perfect diffuser is usually considered to be an achromatic stimulus for all illuminants, except for those whose light sources appear to be highly chromatic.[34]

Color constancy is achieved by chromatic adaptation. The International Commission on Illumination defines white (adapted) as “a color stimulus that an observer who is [chromatically] adapted to the viewing environment would judge to be perfectly achromatic and to have a luminance factor of unity. The color stimulus that is considered to be the adapted white may be different at different locations within a scene.[35]

https://en.wikipedia.org/wiki/White


2,542 posted on 11/06/2019 2:33:31 PM PST by Rusty0604 (2020 four more years!)
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