# Sensation

 The flashcards below were created by user Anonymous on FreezingBlue Flashcards. Monocular Cues to 3d space Relative sizeRelative heightTexture gradientFamiliar sizeAerial perspectiveLinear perspectiveVanishing point Relative Size we assume that smaller objects are farther away from us than larger objects Relative Height Below horizon objects higher in vidusl field appear to be farther awayAbove horizon objects lower in visual field appear to be farther away Texture Gradient Items of same size from smaller images when they are farther away Familiar Size a cue based on knowledge of the typical size of object Aerial Perspective light scatters when it travels through the atmosphereThis scattering of light makes distant objects look fainter, blue, and less distinct than close objects Linear perspective lines that are parallel in the 3d world will appear to converge in a 2d image Vanishing point point at which parallel lines will meet Pictoral Depth Cue A cue to distance or depth used by artists to depict 3d depth in 2d pictures Anamorphosis use of pictoral depth cues to create a 2d image that looks 3d only when viewd from a particular image Motion Parallax relative motion of objects provides distance information. 2 parts to motion parallax 1a. objects in front offixation point move in the opposite direction to you1b. objects behind fixation point move in the same direction as you2. Objects closer to fixation point move more slowly than objects farther from our fixation point Accomodation The amount ofmuscle contraction needed to change shape of the lensgives us distance information 2 Binocular cues 1. convergence2. binocular disparity Convergence amount of muscle tension used to move eyes to an object can be used as a distance cueclose toobservation Binocular disparity (stereopsis) Each eye sees a slightly different view of the worldThis difference is a distance cueThe red line is exactly the same distance from fovea Horopter the area of space where other objects will also fall on corresponding points Corresponding points the retinal images of a single object are formed at the same distance from the fovea in each eye The horoptor has three different situations 1. corresponding points2. non corresponding points3. panum's fusion area Non corresponding points objects that do not fall on the horopter create non corresponding points on each retinaThe further away, the more disparity (blurry)double vision Panum's Fusion Area Small region surrounding horoptorin PFA objects fall on non corresponding points, yet dont create double images Objects that arent on the horoptor or not in PFA will produce; double images Crossed Disparity Created by objects in front of the horoptorImages in front of horoptor are displaced--To the left of the fovea in the right eye--To the right of the fovea in the left eyeThis doesnt happen when image is gehind horoptor its more orderly Uncrossed disparity Created by objects behind horoptor (there is no crossing disparity in eyes)Images behind the horoptor are displaced...--The right of fovea in the right eye--The left of fovea in the left eye(Finger test - 1 farther away/1 closer) 3d glasses Anaglph glassesPolarized glassesShutter glasses Anaglph glasses cheap blue and red glasses Polarized glasses puts color back in to the filmSubtract all light waves that are coming from one direction Free Fusion Converging (crossing) or diverging (uncrossing) the eyes in order to view a stereogram without a stereogram Stereoblindness Inability to use binocular disparity as a depth cueCant see the picture inside the magic eye picture--Can result from a childhood visual disorder, such as strabismus, in which the 2 eyes are misalligned 3 types of Binocular Disparity Cells 1. No binocular disparity2. Crossed disparity3. Uncrossed disparity A cell only responds to a certain kind and amount of disparity Combining depth cues: Illusions and the Construction ofspace our visual systems take into account depth cues when interpreting the size of objectsThe hering illusionAmes Room-2 teddy bearsAmes windowMuller-Lyer illusion (arrows) Ponzo Illusion man on train tracks-actually the same size Reversible Figures/Unstable Figures pictures that can be taken two or more different ways *Nesser cube*Duck rabbit*Seeing black outline figure in a vase*Tessellation Impossible Figures Elephant with too many feetNever ending staircaseWEird triangleFigures that could never happen or be built/done AuthorAnonymous ID111782 Card SetSensation DescriptionSpace perceptiom & Binocular Vision Updated2011-10-24T21:26:39Z Show Answers