This article features excerpts from “Me and My Shadows,” by John Roman, in the May/June 2022 issue of Artists Magazine.
All artists are familiar with the classic perspective example of railroad tracks converging toward a vanishing point, but few are aware that cast shadows also follow that same rule. Plotting how the sun and moon create shadows on a terrain, or how shadows from artificial lights project onto surfaces is a valuable tool in an artist’s skill set. A basic formula exists for drawing or painting shadows in perspective, and it applies to all their luminous combinations.
Ironically, the artists in history who first invented the laws of perspective limited their treatment of light to depicting folds in fabrics and forms of figures. Absent from 13th- and 14th-century Renaissance art is the understanding of how light projects shadows into three-dimensional space. Early painters’ handling of ground shadows was minimal and suggestive at best. Not until the 17th century did artists begin to analyze light projections more thoroughly. Dutch artists of the 1600s were the first to discover the importance of a direct light source and, in their studies, introduced the theory of shadows projecting to vanishing points just like all other parallel lines do.
The best way to learn how shadows work and how to draw them is to familiarize yourself with shadows in real life. Learning the technical rules for drawing shadows in perspective is futile until you train your mind to understand what actually happens when shadows project. When starting out, just observe shadows to see what they’re doing. Take note of whether they’re pointing toward you or away from you. Make a daily habit of studying actual shadows and, perhaps, photographing them. In time, your practice will reveal how perpendiculars that block a light’s path will cast horizontal shadows into or out of a scene. You’ll also see first-hand how shadows observed at an angle (not straight on) converge to a distant vanishing point.
Studying Shadows in the Real World
One way to study shadows is to look for them in your daily activities. Let’s say you’re walking along the shore and you see two people in beach chairs facing the setting sun (see Basic Shadows in Perspective). The first thing that catches your eye are the dramatic shadows cast on the sand. You notice the shadows emit from the people, getting narrower near the people and widening as they come toward you. Now, using your imagination, project those shadows back toward the sun to see where they meet. It’s clear the shadows are pointing to a spot somewhere near the head of the person on the left. That vanishing point is where the horizon line is located behind the beach houses. Once you locate that, look directly above the point to see the source of light: the sun.
The first time you witness this in person is exciting. It’s as if a new world has opened. Most of us are totally oblivious to the array of shadows surrounding us day and night, and your initial experience will encourage more virtual studies. Let’s try it again. This time, imagine you’re sitting at an outdoor café in the morning light, with intricate shadows projecting toward you (see Shadow Projection Formula). You see the shadows converging to a point on the right side of a tree and realize this must be where the horizon is—in the distance behind the buildings. Look directly above that point. The light source peeks between the tree limbs.
Now you’re hooked! Shadow projections are becoming obvious everywhere you go. One day you’re walking through a lobby and see the sun’s rays pouring into the hallway (see Vanishing Point). The window frames, people inside the hall and the person outside on the sidewalk all create shadows aimed at a vanishing point across the street. This marks the distant horizon. Directly above that vanishing point, the sun shines through.
Shadows from indoor lamps and streetlights follow a comparable rule. Artificial lights project
to vanishing points on the ground plane directly below the light source, and shadows are cast from any perpendiculars in the light’s path. Unlike natural light, however, artificial light sources can produce several overlapping shadows (see Overlapping Shadows).
Rules of Shadow Projection
Once your eye and brain are awakened to the behaviors of shadows in the real world, the rules will begin to make sense. It may sound easy, but the intricacies of shadow projections can be vast, complicated, and intimidating. Yet, if you know what to look for, the basic formula for shadows in perspective is always there—even in the most complex scenarios (see Shadows in Perspective).
Three key points lie at the foundation of shadow projections: A) a light source, B) a vanishing point for the shadows and C) shadow projections from that vanishing point when the light source is in front of you, or shadow projections to that point when the light source is behind you. Keep in mind your personal study of shadows is more important than solving every shadow challenge you encounter. Just that you’re engaged with looking for the answers will sharpen your visual skills for understanding the dynamics of shadows.
One final point to consider is the fact that shadows in art are the easiest things to “cheat” at. When someone views a work that depicts shadows, their brain is only looking for basic projections of shadows, not whether shadows are mathematically or accurately rendered. In other words, a lot of artistic license can be taken when drawing and painting shadows. As the artist, you have permission to take liberties with the rules and abandon the technicalities of plotting shadows in favor of accentuating the depth, drama and emotional strength they can bring to your art.