Gustave Caillebote, Paris Street: A Rainy Day, 1877

I just saw this painting in the Chicago Institute of Art two weeks ago and was really impressed by it.  Now I realize that it’s a perfect example of the types of cues artists can use to give their paintings depth perception.

The first and most obvious cue I see in this picture is relative size, which is the angular size of an object as compared with that of another.  Thus, the same objects in the foreground are painted with larger sizes than those in the background in order to recreate the mechanism of the eye in which distant objects create a smaller image on the retina as compared to objects in close distance.  Relative size seems to be one of the most important of the monocular cues of visual depth perception utilized by painters.  In the painting above, you can see the importance of this cue in creating the perception of the three people walking in the very front of the scene, drawn with a larger size, as compared to the perception of the people in the middle and the people in the far distance, drawn with smaller and smaller sizes.  The perceived normal size of the smaller people in the background despite their actual smaller height is due to the mechanism of size constancy (which works in a process similar to the mechanism of color constancy).

Another important visual cue of depth perception in this painting is linear perspective, in which the parallel lines that recede into the distance appear to get closer together or converge.  This cue is what gives the buildings in the painting above their depth and orientation.  The parallel lines of the different floors of the buildings converge to show the depth of the building as they recede into the distance.

Another really cool cue of depth perception utilized in the painting above is texture gradient, which shows that when surfaces with texture get farther away, their texture gets finer and appears smoother.  This cue is seen in the texture of the cobblestone road, which can be seen in more detail in the foreground of the painting but not in the background.

The use of shadows adds much depth perception to a painting, and this can be seen in the painting above.  The shadows of the men in the middle ground add to their perception in the middle of the portrait as compared to those in the foreground, whose shadows cannot be seen because the fall beyond the front of the portrait, and those in the background, whose shadows are so small they can barely be seen.  This is also the cue that emphasizes the position of the lamp post in the very center of the painting.

 Bruegel, Landscape With The Fall of Icarus, 1558

This painting has always been one of my favorites and seems to be a great example of how depth perception can have a symbolic importance.  In this painting, Bruegel intentionally places an ordinary scene in the foreground of the painting, with the more important scene showing the actual fall of Icarus in the far background, to show how as the famous boy drowned into the sea, life simply moved on without noticing. This painting utilizes many cues of depth perception, and an important one to be mentioned is aerial perceptive, which involves the scattering of natural light from the sky to add depth.  The intense hues of yellow near the background of the painting lessen in intensity as light moves to the foreground of the painting, mimicking the natural travel of light.  The slight blurring and blueing of the background also add to the impression of depth.

It’s funny how I’ve always noticed depth in paintings without really analyzing or thinking about exactly what creates such depth in something that exists on a flat sheet of canvas.  I wonder how much intense thought and planning it takes to create such amazing paintings with such awesome depth…

If you want to learn about more cues of depth perception and see more specific examples of paintings that show these cues visit this cool website.