Observations of reflected light with a single light source

During the process of set-up and photography of the four geometric solids in the studio, it became apparent that, even with just one light source, the phenomenon of light reflecting off direct and indirect surfaces into other areas became a significant feature.

Although the practice of cinematography and theatrical lighting utilizes techniques to place light strategically and accurately, the challenge of understanding and manipulating the effects of light with just a single source has offered some unexpected insights for me.

Attached are a series of photographs with the same four solids composed in a variety of configurations exhibiting some different results. Included first are single images of the solids on the ground plane surface as benchmarks for shading and cast shadows.

Fig.01 - Geometric solids with same single light source

Fig.02 - Original composition with light source from left instead of right

Fig.03 - Note the variation in value of cast shadows on different surfaces



Fig.04 - Note the variation of surface light on the sphere in the shading and cast shadows



Fig.05 - Although appearing randomly composed, this image's value lies in the form definition revealed in shaded and reflected surfaces

In the beginning of this project, I assumed that the strongest methodology for modeling three dimensions would focus on a definitive light source using highlights and cast shadows to create contrast. With a background in drawing and design visualization I was surprised by the reduced evidence of edge highlights and surface definition in directly illuminated surfaces. Instead, a much richer variety of light modulation appears to exist in the shading and cast shadows where ambient and reflected light from adjacent surfaces provide softer but distinctive definition.

One of the unintended gains from the photo session has been the revelations in reflected light from one object or surface to another using matte surfaces only. Often in the design process, designers may specify highly reflective surfaces for the product. The downsides to this methodology can be the masking of the true effects of light and the image complexity resulting from bounced reflections.