In the figure above you may also note the appearance of spots in the intersections of the streets separating the colors in the palette. See the Herman Grid Illusion for more information about these spots. Do they appear gray, as in the Herman Grid or do they seem to have tinges of color associated with the adjacent colors in the palette? Are they equally apparent on all backgrounds?
Please note that when you view a succession of images there may be some carry over. You may want to use one eye and then the other for viewing successive images. You may want to wait a bit between viewing images.
The above image was created using 2 yellows and 1 blue. The appearance is that the image has been constructed from more than 2 yellows and 1 blue.
A look at our languages shows that most of us consider color as a property of objects. We talk about 'the beautiful blue sky' or the 'bright red sweater'. The sky is never blue and sweaters are never red. These objects may appear blue, red or some one of the many other colors that we can experience. Saying that you see a color is reporting your subjective experience and not a property of an object.
Our subjective experiences are related to patterns of neural firing in three neural channels of our visual systems. We learn labels for our experiences related to different patterns of neural firing. We label a cloudless sky, or rather our experience of that sky, as blue.
While there are correspondences between the physical world and our experiences of color, these correspondences are not necessarily 1 to 1. Edwin Land, the founder of Polaroid Corporation, showed that the same color experience can result from various combinations of light at different wavelengths. You could look at a screen and see the same color on that screen while the light used to produce your experience greatly differs from one presentation to another.
In the above image the word "COLOR" appears to be constructed from 2 yellows. Only one was used. The difference in the appearance is related to the influence of the backgrounds.
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