Investigation Three: Different Perspectives

In Investigation Three, students complete their formal exploration of perspective. During the PreLab, students can apply what they have learned about perspective and depth perception by creating their own drawings. In addition, they will again discover how the use of vanishing point and perspective in art provides a very important lesson for us about human perception by viewing some optical illusions.

While we may see with our eyes, the meaning of what we see is dependent upon interpretation by our brains. Thus, our experience tells us that objects closer to us tend to be larger and that parallel lines tend to converge as they further from us. In the real world, this allows us to judge distance and the relative placement of objects. Think, for example, of the importance of our brain being able to tell us that a dangerous animal that increases in size as we watch it is moving in our direction!

Notice that, in the animation above, the spider takes up a larger and larger amount of our field of view, and the visual angle it creates on our retina increases as it crawls toward us. Our brain interprets this increase in visual angle as a movement toward us and may signal potential danger and cause us to react accordingly (below).

Now, look at the animation below, in which the visual angle at which we view the spider steadily decreases. This simple change in the visual angle dictates our immediate interpretation of its direction of movement – it appears to be moving away from us.

Keep in mind that both of the spider animations shown here are presented on a 2-dimensional screen. This brain-based process provides essential information about the world around us. Artists have used this phenomenon to provide perspective, depth, and realism in their paintings.

Optical Illusions

Since our brain interprets all that we see it is not too surprising that we can be “fooled” by optical illusions. The illustrations below are good examples:

In the left illustration, the domino is the same size in all three of the depictions. In the right illustration, the unattached yellow horizontal lines are both the same length, although the lower line appears shorter. Such optical illusions work because the vanishing point of the drawing tells our brains that a distance is represented. Our brains then expect that the same object when viewed from further away should appear smaller. Since this is not the case for the dominos or horizontal yellow bars in these illustrations, our brain compensates by interpreting the size of the dominos to increase from left to right and the horizontal yellow bar to appear larger in the distance than in the foreground.

Point of View

In addition to providing a review of perspective in relation to depth perception, Investigation Three also reacquaints students with the point of view aspect of perspective. Point of view can be described as the position of an observer in relation to an object they are observing. When observing an object, event, or scene, the position or angle from which it is observed may strongly influence how people perceive it.

The same or similar object may be perceived differently if viewed from another perspective. In art, there are many different angles from which an artist may represent an object. Depending upon an artist’s interpretation and point of view they choose to use, the artist can persuade the observer inadvertently to see an image as the artist wishes it to be seen. This tactic may be used not only by artists but also in the media, film, and even our daily conversations.

The twentieth-century Dutch graphic artist M. C. Escher made extraordinary use of point of view in many of his captivating works. An excellent example of Escher’s fascination with point of view is shown in his etching called Relativity, created in 1953. Download this print by clicking on it, and then use your computer to flip it around and observe how the point of view changes.

In Investigation Three, students will have the opportunity to view, describe, and draw three objects from four different points of view. What they will discover is that the appearance and description of the objects in relation to one another (right, left, front, back) differ depending upon the location of the observer even though the objects are undeniably the same objects regardless of the observer’s position in relation to them. While this concept is seemingly simple, it is an important concept to master. Understanding this concept provides a basis for understanding the interpretation and observation and analysis of events not only in science and art but also in all aspects of life.

Students complete their investigation by relating the results of their experiments to the depiction of events and objects in a variety of pieces of art.