Color and Motion Perception

Color Perception

• In the United States, red and white are used for emergency vehicles. I think red is used because people associate red with danger and chaos. The advantages of using red is that is easily detected under bright light. and is distinct from other vehicles. While under dim/dark lighting red is not as easily detectable, the flashing lights help with its visibility. White is a great color to use because it is very visible under dark light. However, white emergency vehicles could be mistaken for vans or buses.
• The color of an emergency vehicle greatly affects its visibility and ability to alert drivers and pedestrians. The experience of color depends on the context; our perception of the color of the emergency vehicle changes depending on whether we see the whole vehicle, or if we just see part of it. If we see part of the vehicle under changing lighting, the vehicle will seem to change color. But if we see the whole vehicle under changing lighting, it will remain the same color. This is known as color constancy. As the book said, "You and I see color thanks to our brains' computations of the light reflected by any object relative to its surrounding objects." So, our perception of color is determined by the object and its surroundings. In choosing the color for an emergency vehicle, they should choose a color that is distinctly different than its surroundings in order for it to retain color constancy in different lighting.
• One factor that affects how easy it is to see various colors is the context of the color, which depends on the brightness, relative luminance, lighting/wavelength shifts, and surrounding colors.

After looking at all of the different factors which affect color perception, I think emergency vehicles should use bright colors such as neon-ish red and yellow. Red will be obvious during the day, while yellow will be easily visible during the night. Also, since this combination of colors are not common, the emergency vehicles will be easily detectable and will stand out from the surroundings.

Motion Perception

• We rely on motion perception for everyday life, such as eating, walking, writing, or driving.
• In order to perceive motion, we rely on factors such as sizes of objects. As an object becomes smaller, we perceive it to be moving away from us. In contrast, as an object becomes bigger, we perceive it to be moving towards us. Also, our brains perceive large objects (such as trains) to be moving slower than small objects (such as cars), even if they are moving at the same speed. To form the perception of movement, brains use stroboscopic movement, a rapid series of slightly varying images.