Motion parallax is a monocular depth cue in which we view objects that are closer to us as moving faster than objects that are further away from us. Learn about motion parallax, depth perception, monocular cues, and more.
Look at this image (see video).
What do you see? Most people would interpret the figure in the image as a box or a cube. A box, just like a cube, has three different dimensions: length, width and height. There is something about the way in which the figure is drawn that allows you to to perceive all three dimensions, even though it is drawn on a flat screen which only has two dimensions.It is due to our ability of depth perception, which is the ability to use visual cues in order to perceive the distance or 3-dimensional characteristics of an object.
What Is Motion Parallax?
Motion parallax is a type of depth perception cue in which objects that are closer appear to move faster than objects that are further. It’s a type of monocular cue, a depth perception cue that can be perceived through the use of one eye. This is opposed to binocular cues, which are depth perception cues that can only be perceived through the use of both eyes.Motion parallax occurs when objects that are at different distances from us appear to move at rates that are different while we are moving.
We judge an object’s distance based on how quickly an object moves. The closer an object is to us, the quicker it appears to move. The further an object is from us, the slower it appears to move.The further away we look, the wider our visual field extends.
It follows that objects closer to us have to travel a shorter distance before they are no longer in our visual field. Objects that are farther away have longer distances to travel before we can no longer see them. As a result, they stay in our visual field longer than the objects that are closer. Because the objects that are further away stay in our visual fields for a longer amount of time than those that are closer to us, we perceive the objects that are further away as moving slower and the ones that are closer as moving faster. This creates the motion parallax.
Imagine that you were a passenger in a car looking out the window. You notice that the silver pole appears to move faster than the white apartment building in the distance. This is because the silver pole is closer to you than the white building.It is important to note that motion parallax does not provide any information about the actual distance between you and an object. It only provides information on the distance of an object from you in relation to another object.
In other words, motion parallax cannot tell you how many feet away an object is from you, but it can tell you if an object is further or closer from you than another object.
Motion parallax is a monocular depth cue that causes objects that are closer to you to appear to move faster than objects that are further away. The further away something is, the slower it appears to move. Motion parallax influences how we judge relative distance.