Unit 10: Continued

Today we learned about the difference between specular an diffuse reflection. Specular reflection is when light is reflected off a smooth surface, such as a mirror. Diffuse reflection is when light is reflected off rough surfaces, such as clothing or paper. The law of reflection states that all angles are relative to the normal.

This picture shows three Mr Blakes! We learned how to make this using two light (slide?) projectors and our new knowledge of the colors of light. In kindergarden, they taught us that the primary colors were red yellow and blue. As you can see, the complimentary colors (colors that are on the opposite ends of the color wheel) of these primary colors are orange, purple, and green. All the colors mixed together makes black.

On the other hand, because of photography, I learned about colors for printing; RGB & CMYK! The primary colors are red, green, and blue (RGB). The rest of the wheel makes the complementary colors, CMYK, or cyan, magenta, yellow, and black. Also, all the colors added together makes white. We had an dye sublimation printer, which uses CMYO to print photographs. O is used in place of K (black). The O is for the overcoat film put on the photograph last that protects it from ultra violet rays and discoloration. Dye sub printers are unique because they skip the liquid phase of the ink when printing (ink goes straight from solid to gas).

Color Models Source: http://en.wikipedia.org/wiki/Primary_color

Going back to the three Mr Blake(s)...he has two shadows correct? Two sources of light, (the green projector and the red projector), so two shadows. One source of light, one shadow. Red and green light, as we now know, makes yellow. This is why the board is yellow. The shadow on the right is red. This is because the red projector is on the right side. His body is blocking the green light coming from the left. Yellow = Red + Green

Yellow - Green = Red

Red shadow. 

The same thing happens on the other side. The green projector is on the left. His body is blocking the red light, so:

Yellow = Red + Green

Yellow - Red = Green

Green shadow.