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Current time:0:00Total duration:3:49

Video transcript

so far we've been talking about color in terms of wavelength of light and human color receptors that's the physics part of color now let's turn to the perceptual part we just learned that every color has a hue saturation and lightness but colors appear in our world alongside other colors and that can really affect how they appear it's also when things can get really really weird for example look at this image notice the two inner color rings the one on the left looks green the one on the right looks blue there are different colors right nope if you take away the other colors you'll see that they are in fact the same color and it's not only color which can trick us different brightness levels will also affect how we perceive an image for example look at the following grayscale image take a closer look at these two squares a and B one is a black square in the light the other is a light square in shadow do you think they are different shades of gray nope let me show you they are in fact the same shade of gray so clearly not everything is what it seems how we perceive contrast or brightness depends very much on the surrounding image and it brings us back to how the brain processes incoming image signals the structure of our visual system is optimized so that we can do important things like survive but a key survival trait is the ability to very quickly identify danger this requires the ability to rapidly refocus our attention when we need to our brain does this by automatically refocusing our attention to dramatic changes in color brightness or movement we call this difference in color or illumination contrast our brains are hard-wired to notice when the colors contrast with each other in the color mastering suite we can adjust the contrast of an entire image using a contrast slider it works by increasing or decreasing the differences in brightness or the illumination levels across the image for example notice the left half of this image has a lower contrast level than the right half getting this contrast level right is really important in Pixar movies for example at the end of Inside Out in the headquarters there's a scene where the character anger gets really really angry and to sort of heighten this sense of him flames exploding from his head the surrounding area of the image is darkened so that the the contrast difference is really quite extreme in that moment these kinds of decisions are made by the director of photography and casually we refer to them as the DPS any decision that involves colors or lighting of any kind will involve the DP another great example is from the movie Toy Story 3 lots of the bear is sort of in this whole sequence been the only really pink thing in the scene it's very much about an emotion of love between lot Zoe's owner and and the bear and then as as the bear is lost as a scene at the end where Lotso is looking in the window at Eddy's owner and the replacement bear and then what we're trying to do there is sort of have lots of the original seem far less pink than the new bear which is very much now the sort of center of attention of love and that you know hiding that perception of that difference between how pink each of them are was very much central to the emotion in the next exercise you'll have a chance to play with contrast