Drawing with the Sight-Size Method

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Drawing with the Sight-Size Method

Source: Mainly based on materilal from Ben Rathbone, a representational painter working in the Classical tradition ( http://480bc.com/)



The Sight Size Method is a method of constructing realistic drawings with great accuracy that has been used to draw and teach drawing for centuries. It is a method by which anyone with any amount of drawing experience can set up and execute a realistic drawing. I will describe the method in terms of drawing on this page, but the method it can be used for drawing or painting and can be applied to portraits, figures, a still life, a cast, or any stable scene.

Basic Ideas

The basic idea on which this method depends setting up a specific relationship between you, the drawing, and the subject. The relationship necessary for the method to work is where you are positioned so that you can easily view the subject and drawing so they appear to be the same visual size. Once the subject and drawing are seen as being the same size, it becomes possible to mechanically measure and compare the proportions of the subject to the drawing and judge the drawing’s accuracy. The process of engaging in this method, over time, trains the eye to perceive finer and finer deviations in form between the subject and drawing and increases the artist’s ability to create realistic and accurate drawing.

To illustrate the basic idea, imagine standing inside a house on the ground level. Imagine looking through a large window to the front yard at a person standing outside about 20 feet from the window. If you stood at arm’s length from the window, you would be able to place some tape on the window, where you see the top of the person’s head. You would also be able to place some tape on the window where you see the person’s feet, fitting the person between the marks. Or, imagine a straight laser-like line going from your eyeball, through the window, to the top of the person’s head. Imagine a second straight laser-like line going from your eyeball, through the window, to the bottom of the person’s feet. Now imagine placing some tape where the first line intersects the window as well as where the second line intersects the window. You will have marked the visual height of the person as they appear on the window. If you remained in the same position, and the person outside moved further away from the house, and you placed new marks, the marks would have a smaller distance between the tape marks. Now imagine taping a sheet of paper to the window, next to where you see the person and have placed the tape marks. The crux of the sight size method is getting the person to ‘fit’ on to the paper you have taped to the window and having the distance between the tape-marks correspond to the size of the drawing you wish to create on the paper.

In a studio setting, if you were drawing a model, the position of the model would be fixed, but your drawing and your position would be movable. To get the model to fit on your paper, as you moved away from the model, the model’s visual size would become smaller. Plus, the distance between you and the easel can be varied to alter the size of the drawing corresponding to the model. As the easel is moved closer to the model, the size of the drawing would approach the actual size of the model. I’ll be describing below how I used the Sight-Size method to execute a highly-rendered charcoal drawing of a plaster cast. I did this in 2001 at the School of Representational Art in Chicago. In this case, and in the case of most cast or still life drawing, the easel is placed close to the cast.

Tools Needed

The tools needed are a long ruler or T-square, string, easel, drawing paper, and whatever drawing medium is desired. The drawing medium can be anything: pencil, pen, pastel, or paint. In the case of this cast drawing, I had a wooden stand on which I placed a black cloth, and then the plaster cast on top of that. I used grey-toned paper on a vertically mounted board behind the cast to create a grey background. I mounted my paper (Canson Mi-Tentes) on a large flat board and placed this on an easel. Then I created a plumb-line by tying a large hex-nut to a piece of string and tying the string to a wooden rod that I suspended above the cast. This creates a nice, stable vertical line in front of the cast that will be useful in the process of drawing. Another item needed is something to take measurements. The traditionally item is a knitting needle or another long and straight object where a distance can be noted by placing the thumb on the needle. I’ve always preferred and used a compass, the type used to measure distances on a map, such as found in this kit.

Figure 1: This shows the cast set up directly to the left of the drawing paper.

First Step: Setting Up

The first step is to get the set up your cast, paper, and your vantage point. The cast needs to be positioned so the midpoint of the cast is at your eye level when standing. The paper needs to be mounted on an easel with the midpoint of the paper at the viewer’s eye level. Be sure that you have enough space on the paper to comfortably fit the cast and everything you want to draw. The paper should be mounted as straight and perpendicular to the floor as possible. The paper should also be positioned in front of the cast. Imagine the paper creating a flat geometric plane perpendicular to the floor and perpendicular to your eye level when standing. The drawing surface should be pulled forward so that the plane does not intersect with the cast. For the sake of this cast drawing, I used a single light source and blocked off all light in the room.

Now, stand in front and in between the cast and paper and take several large steps back. Position yourself so that by standing normally you can take in both the cast and your paper without moving your head and minimally moving your eyes. Your vantage point should be about 3 times the height of your cast. This is your ‘vantage point’. It is from here that you will be able to look at the cast and your drawing, and have both appear to be the same size. Once the vantage point has be established, it should be marked on the floor, usually with masking tape, so that you can easily find the exact vantage point again. Once all of this is established, you are ready to begin drawing.

Figure 2. This describes holding up a string horizontally to create a line that extends from the cast onto the paper.

Figure 3. Illustrates reference lines and marks

Second Step: Initial Marks and Reference Lines

To start the drawing, the first thing I did was to to establish the initial reference lines to aid the basic construction of the drawing. One can think of these as the scaffolding on which the full drawing will be built.

To do this I stood at the vantage point and with string, fully extended both arms pulling the string into a straight horizontal line. Keeping the line horizontal, I raised the string until it touched the very top of the cast head. The middle of the string was between the cast and your paper. I made a mental note of where the string intersected the edge of the paper closest to the cast. Then I marked this point on the paper, close to the edge. Since the distance between the vantage point and my paper was quite large, there was always the chance that I would not place the mark in the right spot. So, after making the mark, I stepped back to the vantage point, and checked the mark. I did this by extending both arms, holding up the string in a horizontal line, and raising the string to where it touched the top of the cast. I then compared this with where I had made the mark. If the mark was too high or too low, I would make a mental note of the amount of adjusting needed, and would walk back up to the paper and move the mark. The result will be a series of marks on the left-most edge of the paper, which prepare you for the next step.

Third Step: Establishing Reference Lines

When five or six of these marks were in place, I took my ruler (in this case a large level), placed it horizontally on the paper, and extended a line across the paper from each mark. Figure 4 illustrates this. The result was a series of horizontal lines on the paper. Next it was time to decide where the vertical center line would be. The vertical center line would correspond to the plumb-line string that I had set up. The center vertical line on the drawing can be anywhere, provided there is enough space on the paper on either side for the cast as well as extra space so that the whole drawing has a pleasing composition. So I accounted for this and picked a spot for the vertical line and drew it in with the level, held vertically.

Figure 4: Drawing horizontal lines to create reference lines from the marks made on the left of the paper.

Now I had a series of horizontal lines and a vertical line. These lines were the scaffolding for my drawing. From here I was able to begin placing very basic lines to establish the big shapes of the cast. Figures 5, 6, and 7 show how I used these basic lines to judge a specific width, in this case, the width of the head. The width of the head on the cast can be divided into two smaller widths in reference to the plumb line. Figure 5 shows a point on the cast, above the eyes, in the middle of the cast’s forehead and how it corresponds to a spot on the drawing.

Figure 5. Shows two points that correspond on the cast and the drawing.

Fourth Step: Drawing and Measuring.

To make a specific comparisons, I used (and still use) a drafting compass. This is my tool of choice, however most people use a knitting needle and their thumb. I’ve always liked the compass as one can extend it to measure a length and once it is extended, it retains that length. To check a measurement on the the cast, I returned to the vantage point. Figure 6 shows how I would extend my arm and hold the compass. I would extend the compass to gauge the length from the point on the plumb line to the edge of the head. Once the compass has fixed this length, I simply moved my extended arm over to the drawing and checked if my line was in the right place. If the lengths matched up, then I knew that half of the total width of the head was correct as compared to the actual cast.

Figure 6. Using the compass to measure a width on the cast.

Figure 7. Using the compass to check the width on the drawing.

I repeated the process of taking measurements and comparing lengths on the cast to what I had in my drawing constantly. I used, and this process can be used to judge all kinds of lengths, widths, and spatial relationships. It can be used to not only judge positive space relationships, but negative space relationships as well such as the space between the knees, or the space between the elbow and torso, or the chin and the chest, etc. Once I had drawn basic lines to outline the cast, I used the same process to draw and then check lines for the shadow shapes and features.

Figure 8. Preliminary charcoal drawing.

Figure 9. Final fully rendered drawing.


I’ve described the Sight-Size method in terms of academic cast drawing. Academic cast drawing, and the process of taking a drawing to a level of almost photo-realistic level of rendering is outside the scope of this page and separate from the Sight-Size method. The basic process of fixed vantage points and taking measurements between subject and drawing can be used for any kind of art where representation is a goal, for almost any subject matter. As an person employs this method more and more, one develops the ability to see and make finer and finer shape and form discriminations. The ability to see finer and finer deviations between the subject and drawing is what enables the ability to execute drawing with increasing accuracy.


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