Apparent motion
Encyclopedia
Apparent motion may refer to:
In astronomy:
In perceptual illusions:
Other uses:
In astronomy:
- Apparent retrograde motion, the appearance that objects in the night sky move against the typical direction of motion
- Improper motion, any effect which appears to cause the position of a celestial object to move
- Aberration of lightAberration of lightThe aberration of light is an astronomical phenomenon which produces an apparent motion of celestial objects about their real locations...
, improper motion due to the finite speed of light and the motion of Earth in its orbit around the Sun - Diurnal motionDiurnal motionDiurnal motion is an astronomical term referring to the apparent daily motion of stars around the Earth, or more precisely around the two celestial poles. It is caused by the Earth's rotation on its axis, so every star apparently moves on a circle, that is called the diurnal circle. The time for...
, improper motion due to the Earth's rotation on its axis - ParallaxParallaxParallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines. The term is derived from the Greek παράλλαξις , meaning "alteration"...
, improper motion caused by the Earth's orbit around the sun
- Aberration of light
In perceptual illusions:
- Beta movementBeta movementThe Beta movement is an optical illusion, first described by Max Wertheimer in 1912. Its illusion is that fixed images seem to move, even though of course the image does not change. It might be considered similar to the effects of animation...
, an illusion of movement where two or more still images are combined by the brain into surmised motion - Illusory motionIllusory motionThe term illusory motion, also known as motion illusion, is used to define the appearance of movement in a static image.This is an optical illusion in which a static image appears to be moving due to the cognitive effects of interacting color contrasts and shape position.Another type of motion...
, the appearance of movement in a static image - Phi phenomenonPhi phenomenonThe phi phenomenon is an optical illusion defined by Max Wertheimer in the Gestalt psychology in 1912, in which the persistence of vision formed a part of the base of the theory of the cinema, applied by Hugo Münsterberg in 1916....
, an illusion of movement created when two or more adjacent lights blink on and off in succession - Stroboscopic effect, a phenomenon that occurs when continuous motion is represented by a series of short or instantaneous samples
- Wagon-wheel effectWagon-wheel effectThe wagon-wheel effect is an optical illusion in which a spoked wheel appears to rotate differently from its true rotation. The wheel can appear to rotate more slowly than the true rotation, it can appear stationary, or it can appear to rotate in the opposite direction from the true rotation...
, temporal aliasing effect in which a spoked wheel appears to rotate differently from its true rotation
- Wagon-wheel effect
- The illusion of movement deliberately sought by certain forms of op artOp artOp art, also known as optical art, is a style of visual art that makes use of optical illusions."Optical art is a method of painting concerning the interaction between illusion and picture plane, between understanding and seeing." Op art works are abstract, with many of the better known pieces made...
(optical art)
Other uses:
- Optical flowOptical flowOptical flow or optic flow is the pattern of apparent motion of objects, surfaces, and edges in a visual scene caused by the relative motion between an observer and the scene. The concept of optical flow was first studied in the 1940s and ultimately published by American psychologist James J....
, a term used in computer science for the apparent motion of objects in a scene caused by the relative motion between an observer and the scene - The motion of objects observed from a non-inertial reference frameNon-inertial reference frameA non-inertial reference frame is a frame of reference that is under acceleration. The laws of physics in such a frame do not take on their most simple form, as required by the theory of special relativity...