Light & Shadow
The ability to understand how light falls on an object or penetrates an environment is a critical skill for both rendering and showing the absence of light – shadow. Although the framework for projecting light onto an exterior or into an interior is the same as the framework for perspective drawing, many students find it a daunting task to learn and therefore often shy away from it. However, with the ability to understand a how to position a light source and how to project it's highlights and shadows will greatly improve your ability to enhance form and strengthen the visual interest within a visual communication.
Most books on rendering or shadow casting require the reader to assume that a product or environment is always rendered using a light source that is slightly in front and above the right or left hand side of the product or environment. Although these positions are great for the external features of products or environments, they don't allow for intricate detail of interiors and inhibit the understanding of how where highlights and shadows are actually come from. Being able to creatively project light from angle in order to create dynamically lit products or environments is a fundamental skill for a designer's tool box.