Monocular Cues

Relative Size is a perception which allows you to determine how close objects are to an object of known size.

 

This picture of flowers in a field displays the sensory perception of relative size, because, we know how big the front flower is and based upon that size we can determine the distance between the front flowers and any other flower.

Relative height is perception where distant objects are seen or portrayed as being smaller and higher in relation to items that are closer.



http://catnaps.org/islamic/islaurb4.html

This picture displays relative height because as we look at the palm trees they look like their normal size, but as we look in the background at the city, the palm trees appear to be bigger than the skyscrapers due to the palm trees being closer and the skyscrapers being much further away.

Relative motion refers to the motion or speed of any object in respect to a particular point.




http://lrosedai323visualdesignliteracysfsu.blogspot.com/2009_04_01_archive.html

This picture shows relative motion, because as we focus on the train, the speed of the background "passing by" allows us to determine the relative motion or speed.