2. Point of View
Perspective drawing refers to the representation of things as they
are arranged in space and seen from a single point of view. The
central issue in perspective drawing is the artist’s bodily position
in relation to the things represented.
A fixed viewpoint is an important achievement in a drawing. This
will affect perspective, proportion, and composition.
3. When looking at a drawing or painting, we tend to identify with the implied
point of view; that is, we know whether the artist was looking up, down, or
straight ahead.
Looking down Looking up
4. Cone of Vision:
A conical volume that constitutes the three-dimensional field of vision.
Its apex is located at eye-level; its base is within the imagined picture
plane.
5. Fixed Position
Before learning the rules of perspective, students often combine
what they see with what they know. The first drawing shows
some common mistakes: it combines what is known (the table is
square) with what is actually seen (three out of four table legs). In
this way, image (a) is showing two viewpoints of table. Image (b)
shows the table from a fixed position. Notice that you can still tell
that the table is square, even though it is not drawn that way.
6. By shifting your point of view, you also shift your perspective. Look at the
differences between these three drawings. They are all drawn from the
same distance and position, but the artist has shown the changes that
occur when viewed from straight ahead, slightly above, and below.
7. These shifts in the shapes occur when your eye level changes.
Eye level is the height your eyes are located in relation to a ground plane.
8. Convergence:
One of the central concepts of
linear perspective is that
parallel lines in nature appear
to converge (come together)
as they recede.
The apparent convergence of
parallels occurs at eye level.
10. Diminution of Objects:
When observing two subjects that are the same size but different
distances from the apex of your cone of vision, the closer subject will
appear larger. The subject farther away will appear smaller. This is
because the farther away a subject gets from the apex of your cone of
vision it takes up less space in the field of vision.
11. In this image, both the convergence of parallel lines is obvious
and the diminution of objects of the same size. Notice how
the poles supporting this arch get smaller and closer together
as they recede in space.
12. One-Point Perspective
Vanishing Point:
This example of railroad tracks is a classic example of one-point perspective.
If you were to stand in the center of a straight stretch of railroad track, you could
look down the rails until they appear to finally converge. The point of convergence
is called the vanishing point. Presuming the ground is flat, the vanishing point will
be located on the horizon line.
13. Eye level and the rate of convergence:
If you had a view of the track from the top of an engine, you
would see the tracks converging at a slow rate toward a high
vanishing point (a). If, however, you were tied to the railroad
track, you would see the tracks converging sharply to a low
vanishing point (b).
14. When creating a one-point perspective drawing, select an area that shows parallel lines
converging and diminution. Consider your eye level. Mark this on the page as your HORIZON
LINE.
15. Next mark the point on your horizon line where your parallel lines will converge. This is your
VANISHING POINT.
16. Now you can begin to mark the converging parallel lines on
your page. You should always use your ruler to make your lines
straight and accurate.
17. The boxes to the left to the tracks in the one-point perspective example have
one face perfectly aligned parallel to the picture plane. This is a limitation of
one point perspective. Another problem with this technique is that objects
become more distorted the further they are from the vanishing point, as can be
seen with the far left box in the example.