CHAPTER 8. PERSPECTIVE
What distinguishes realistic painting and drawing from other forms of visual art is the illusion of atmosphere or distance. Perspective provides an important part of that illusion. There are three kinds of perspective––linear, atmospheric or aerial, and the perspective of detail.
In linear perspective, objects appear to diminish in size as they become more distant. In atmospheric perspective, objects become bluer or more violet as they recede, lights become darker and darks lighter until, in the far distance, all things appear to be a flat blue or violet. This, of course, is caused by the atmosphere between the observer and his subject. In the perspective of detail, details which are quite apparent in objects nearby become more and more vague in objects that recede into the distance. Perspective of detail is actually a combination of linear and atmospheric perspective, but it is sometimes helpful to think of it separately. See Figure 39.
Architectural renderers and engineering draftsmen require a very exact knowledge of scientific perspective, but for the creative artist a general understanding of its principles is usually enough. Often, in fact, it is desirable to violate the rules of perspective in order to achieve a particular effect for reasons of design or emphasis. For those who wish a more thorough knowledge of perspective, there are many books available. A particularly good one for the artist is Creative Perspective by Ernest W. Watson (Reinhold).
ESTABLISHING THE PERSPECTIVE OF A SCENE
To lay out a scene in proper perspective, we must assume that it is being viewed by an observer in a fixed position, looking in a certain direction––for any change of position will change the pattern of the lines. See Figures 40 and 41. We assume that the observer is sitting or standing upright and that his line of vision is level and does not change. The position of the observer’s eye is known as the station point; the center of vision is the point at which he is looking; the line of vision is an imaginary line that runs from the station point to the center of vision. See Figure 42.
The horizon line is a horizontal line drawn across the paper on a level with the eye of the observer; it changes with the observer’s changing position, as shown in Figure 40. Vanishing points are the points on the horizon at which receding parallel lines (that is, perspective lines) appear to converge. There can be more than one vanishing point, but no matter how many, all will be on the horizon line. For example, the perspective lines of a house viewed from an angle will have two different vanishing points on the horizontal line––one on the left and one on the right.
In my own painting, I seldom lay out mathematically correct perspective lines unless a complicated architectural subject is to be depicted. For a group of houses, I simply draw the most prominent house as it appears, say about like A in Figure 43, assuring accuracy of the angles by holding the pencil at arm’s length and testing it against the lines of the subject. Next, I decide where my eye level is on the house. If I find that it is one-third the height of the house, I put a mark there and draw the horizon line across the whole paper (B). Then, drawing lines through the various corners of the house, I find where the vanishing points are (C). Finally, using those vanishing points and the horizon line, I draw in other details of the house and neighboring buildings (D).
Ordinarily, this layout work is done freehand and in less time than it takes to describe the procedure, but until the beginner has had some practice along this line, it may be advisable to use a straightedge, at least for the principal lines.
Several paintings reproduced in this book represent special problems in perspective. Architectural subjects, for instance, usually require more careful perspective layouts than landscapes. In the portrait of “St. Patrick’s Cathedral” on page 51, you will notice that all vertical lines slant inward and tend to merge at some point in space above the spires. This not only is in accordance with the effects of perspective commonly observed when one looks upward, it also is a compositional device to carry the eye to the steeple tops, thus stressing the structure’s height.
“A Street in Alfama” on page 42 was another kind of exercise in perspective. It was only by a very calculated perspective layout that the street was made to run downhill.
PLACING FIGURES IN A PICTURE
Normally, we pay more attention to a living figure than to any of a picture’s other component parts. A figure is noticeable out of all proportion to its size, shape, or color. It may appear more impressive than a building or a tree many times its size. Because of this phenomenon, we must exercise the greatest care in placing a figure in a pictorial composition or its prominence may completely upset the picture balance.
When figures are secondary parts of the scene, I usually insert them as the last details in the composition. To decide on the correct position for each figure, I place a piece of transparent acetate over the picture in the general location I wish to place it. Then I paint a tentative, roughly indicated figure on the acetate. When I am certain of what I want, I paint the figure correctly on the paper.
In the long run, this method saves a great deal of time. It also saves the surface of the paper and the freshness of the aquarelle, for all experimentation is done on the acetate and no actual painting is started on the paper until I know exactly what I want to do.
The beginner is often confused by the problem of indicating the correct pictorial size of figures in relation to each other. Placing and sizing figures is simply a matter of elementary perspective, the same linear perspective that applies to buildings and other structural masses. You can understand more easily the relative size of figures spotted throughout a picture if you visualize a file of soldiers extending into the distance and remember that lines drawn through their heads and feet will converge at a point somewhere on the horizon. See Figure 44. Drawn in this manner, each soldier will be the correct size for his position in the composition.
The same rule applies when figures are scattered about the picture in apparently accidental spacing. If you retain two soldiers of the file, widely separated from each other, then erase the two perspective lines and all the other soldiers, there will then remain no apparent connection between the two figures, but their relative sizes will be correct.
Again using the file of soldiers, you could move them across the paper to the right or left and their sizes would still be correct. Perspective causes the pictured size of any object to diminish as it is carried farther from the observer’s eye, but all objects of the same physical size that stand on a horizontal line will all be of the same size in the picture.
Figure 45 shows how this principle can be applied when spotting figures in various parts of a picture. Knowing that lines drawn through the heads and feet of any straight file of figures must meet at some point on the horizon, insert the largest figure, that is, the largest in pictured size, what you consider the correct position in the picture. You can calculate its size by comparison with nearby objects.
Now, to insert another somewhat more distant figure, make a dot with a pencil where the second figure must stand. Then, from the feet of the first figure (lower right), draw a straight line through the new dot using a straightedge and a pencil and extending it until it hits the perspective horizon. Mark another dot there. You already have the position of the feet of the second figure. From that locating dot, draw a vertical line upwards until it reaches your second diagonal. The length of that vertical line will show the exact height for a figure standing in that position. In fact, a vertical line drawn anywhere within the two diagonals will give the correct height for that location. Repeat the process, remembering that you can run the diagonal lines from either the original figure or any of the newly established ones. The diagonal lines must always converge on the horizon line.
These calculations are based on the supposition that all figures are of the same physical height. If you wish to indicate a smaller or larger person, raise or lower the head. Do not change the position of the feet, for that would change the location of the entire figure. Adjustments must also be made in the drawing if the terrain varies from absolute level.
TO DIVIDE RECEDING DISTANCES
Occasionally you may want to draw a series of evenly spaced or similarly shaped objects along a receding line. The rules of perspective can help you to place them accurately.
Figure 46, for instance, shows how to add seven evenly spaced trees between two established trees some distance apart. Draw lines through the tops and bottoms of the two trees, with the lines meeting at the appropriate vanishing point. Now divide evenly the line AC so it is marked off with nine points. From each point, draw a line to the vanishing point. Next, draw a diagonal from C to B (or from A to D). At the points where the diagonal and the vanishing points cross, draw vertical lines. Notice that the pictorial space between them gets smaller as they recede into the distance.
The same formula can be used to divide accurately any receding distance. If, for instance, your layout shows a simple building and you want to add a series of similar adjoining ones, you can determine the lateral measurements of the addition ones as shown in Figure 47. The heavy lines indicate the original building. Continue lines AB and CD to their vanishing point. Insert line EH (E is exactly halfway between B and D). Construct line CF, running it through E. At F, drop a line vertically to point G. This line shows the exact pictorial width of the next building. The process can be continued as far as desired.
PERSPECTIVE OF SHADOWS
The shadows cast by trees naturally follow the rules of linear perspective. The trees and posts shown in bright sunlight in Figure 48 have been simplified to demonstrate the point.
To lay out the shadows accurately, drop a line from the sun, which may be above the top of the painting, until it strikes the horizon line. From that point, with a straightedge, draw lines passing through the bases of the trees or posts and others from the sun across their tops. The projections will correctly indicate the shadow positions. Note that the shadows become wider as they approach the viewer.
THE RULE OF REFLECTION IN WATER
Smooth water makes a nearly perfect mirror. In a landscape picture the reflections are painted as though there were really an inverted panorama under the shores of the pond or pool. This is confusing to many artists. Knowing that a mirror reverses everything perfectly, they trace the scene already depicted on the paper, reverse the tracing, then paint the inverted details as mirror images of the upright ones. This seems quite plausible, and would be accurate were the artist’s eye level exactly at the water level. Few pictures, however, are painted from that position. Ordinarily, the artist’s eye level is at a point four or more feet above the ground. While it is true that each part of the scene is reflected in exact reverse, one must reckon with perspective and the eye level of the artist. The details do reverse themselves, but the landscape beyond the water does no reverse itself as a unit.
The rule for landscape reflections in water is that any object above water will reverse itself along the horizontal line of its own base at a level where that base would be if the water extended back that far.
What this rule means is that each separate silhouette observed in a receding scene––a scene containing quiet water in the foreground––has the base if its own reversal at a different level in the picture. As details recede into the distance, they are indicated on the paper at progressively higher points.
When a landscape recedes, it recedes continuously, that is, there is no physical break in the actual terrain. But visually a landscape consists not of an unbroken surface, but of a series of separate outlines, or silhouettes, set one beyond the other like stage scenery. In Figure 49, for example, just beyond the farther edge of a pool there is a horizontal row of low bushes, and beyond that, running from left to right, a sandy ridge. Then there are several groups of large trees, and in the distance a line of mountains rising from the far edge of the plain. Beyond the silhouette of the mountains there are clouds in the sky.
Now to reflect these things accurately in the foreground pool it is necessary to think of each of these silhouettes separately, as painted stage settings. The upright painted scene, as an entirety, will not reverse itself. But each of the silhouettes will reverse itself, separately from the others, on it own horizontal base line, and its base line is at water level. If the low bushes, for instance, are growing on ground six feet above water level, the base line is not the bottom line of the bushes, but a point six feet down in the ground.
Now, having established that base line, make a tracing, either literally or mentally, of the bushes, reverse the tracing on the line just mentioned, and paint in that part of the reflection that falls within the pool area. Then move forward again into the scene (that is, slightly upward in the picture), establish the horizontal base line of the sand banks at water level, and repeat the process of reversal. You will notice that much less of the sand bank appears in the pool reflection than shows in the upright scene, die to the constantly rising reversal lines of the receding silhouettes. Continuing upward in the picture, the tall trees will show somewhat in the water reflection but of the distant mountains no trace will be seen in the water. They are too high in the picture. The clouds in the sky should be reversed on a line coinciding with the picture horizon (that is, a line level with the artist’s eye). As for the colors of reflection, remember that they are somewhat darker than those of the scene itself.
So much for smooth water. Should the water be undulant or rippled, the reflections will be distorted accordingly. The inverted image will then consists of a series of separate, small, horizontally shaped reflections, each representing the near surface of a single undulation. These individual reflections will be separated from each other by bands of light where the crests of the undulations mirror the sky. The reflection as a whole pattern will extend downward in the picture considerably lower than the actual scene extends upward. The greater the activity of the water, the longer or deeper the reflections will show in the picture.
As water becomes increasingly rough, the reflections lose their definition, until nothing remains to suggest object reflections other than vague color forms. Very rough water usually corresponds to the color of the sky––blue sky, blue water, gray sky, gray water––and the water is much darker in value than the sky.
Figure 39. Linear and aerial perspective, plus perspective of detail, project the eye into the extreme distance.
Figure 40. Height of Eye Level. Perspective changes as the center of vision is raised or lowered. D shows a house as seen when the position of observer’s eye is only a few feet from the ground. In E, the eye level is about at the eaves. In F, the entire house is seen from above.
Figure 41. Distance From Subject. The acuteness of the angles of perspective changes according to the distance of the observer from the subject. A shows a close-up view of a house. B is a more distant view of the same house. C is a telescopic-camera view of the house form a mile away.
Figure 42. Perspective Drawing. To construct the perspective view shown in the bottom drawing, we begin with a ground plan of the house. We wish to draw the house on a flat plane indicated by the line CD. First, locate the station point (the position of the observer’s eye) at an arbitrary distance from the plan (which represents the building). To locate the vanishing points, extend two sides of the plan to the line AB at the top. Drop two perpendiculars to the horizon line; the two points of intersection are the vanishing points. The farther away you place the line AB from the plan, the farther apart the vanishing points will be.
Next, draw lines from the station point to corners of the plan. At the points where these lines intersect the picture plane, drop perpendicular lines which establish the width of the house.
In most landscape drawings, the exact heights of buildings are not known and the artist must use his visual judgment to establish height.
PORTRAIT OF EILEEN. Collection National Academy of Design, New York.
STREET IN LA ALBERCA. 21” x 29”
THE OLD TOWN, GERONA. 21” x 29.” Courtesy Parrish Art Museum, Southampton, New York.
DAY IS DONE
MOORISH GATE, CARMONA. 21” x 22”