The Human Eye can Detect....

OK, I have to take issue with your statement. :p I've read that the human eye can only distinguish between about that many hues (though I've always seen approximately 150 as the number bandied about), but hue is only one component of color. Color is often modelled as a combination of hue, saturation and brightness. We can distinguish between about 500 different brightness levels. I don't know how many saturation levels we can distinguish, but if my memory is correct, we're a little worse at distinguishing saturation than we are at hue, so let's say 100 levels.

Putting it all together:
150 * 500 * 100 = 7,500,000 colors

So, really approximately, the average human should be able to distinguish between about 7.5 million different colors.

- Madeline (in Professor Maddy mode)

PS: If, in your message, you meant color to just mean the hue, then I guess we're basically both saying the same thing, and I'm just being a lot more wordy. :o
 
They say that all animals like us humans for example only see in grayscale, but that humans can actually perceive color. Now if that's the case, then why do birds have all those bright colors?

Cheers :)

AJ
 
They say that all animals like us humans for example only see in grayscale, but that humans can actually perceive color. Now if that's the case, then why do birds have all those bright colors?

Cheers :)

AJ

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So the question would be, do birds perceive color also? And then their ancestors the dinosaurs?

Cheers

AJ
 
Birds may be able to,but just as if maybe they were color blind,and just saw the different shades of grey and think oh my that male over there is cute. But we really can't tell if they do or not because we can't exactly go up to a bird and ask them, Do you happen to see in color or greyscale?
 
OK this was part of my old job( I did color prints at a photo lab), the human eye can detect between 1 and 2 million colors.
 
This should be an interesting discussion to watch. Red, blue and yellow are the three pigment primary colors, but (and I may be mistaken here), the primary colors for light are red, green and blue (RGB).
In pigmentation, there is no combination of red, blue and yellow that will give you the color of white. White is the lack of color when speaking of pigmentation.
And now for the disagreements and corrections to continue :wave:
Mike
 
There are only three colours: Red, blue and yellow. Any other is a combination of the three.

To a human eye there are no individual colours, just various wavelengths within a spectrum.

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There are only three colours: Red, blue and yellow. Any other is a combination of the three.
The three primary colors are not, Red, blue and yellow, they are Red, Green and Blue, btw.
All colors or lack of colors are based on these three colors.

:)
 
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The concept of three colours arises because of the way the eye works. There are three chemicals that react to light in the cones of the retina. On a graph they peak in red (with a minor peak at the blue end), green and blue. What we see is not pure colours because of the overlap of these curves. A very good demonstation of this was shown to us during my undergraduate days studying Physics. In the darkened lecture theatre a slide of red and blue rectangles was projected with a powerful arc lamp projector. This was then replaced by a green slide and we momentarily saw an out-of-this-world intense green before the red and blue recovered. Another point of interest is that the sensative rods in the eye only respond to intensity (e.g. black and white) which is why we see only in black and white in moonlight but a colour photo will be full colour. Many animals do in fact see in colour but not interestingly bulls so changing the red rag for another won't help!
 
They say that all animals like us humans for example only see in grayscale, but that humans can actually perceive color. Now if that's the case, then why do birds have all those bright colors?

Cheers :)

AJ
so they dont fly into each other:hehe::hehe::hehe:
 
They say that all animals like us humans for example only see in grayscale, but that humans can actually perceive color. Now if that's the case, then why do birds have all those bright colors?

Cheers :)

AJ

Birds can see colour spectrums that humans can't see. For instance the black looking spots on a budgies bib show up as bright violet to a female budgie, and the brighter they are the more desirable is the male as a mate. Humans see these spots as black but they are actually ultraviolet.

Cheers,
Bill69
 
Colour perception depends greatly on neighbouring colours. For example, the difference between two shades that vary only very slightly is immediately apparent when they are adjacent. That is why such a huge range of colours are required to realistically display gently graduating sky and human skin tones, otherwise "banding" will occur.

There are a number of optical illusions which illustrate the effect of neighbouring colours on colour perception.

The RGB effect is indeed physiological, caused by the three types of cone cells in the retina.

Unless anyone knows different, of course.... :)

John
 
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