Butterfly Vision: Robert E. Silberglied’s Photographic Explorations

By Emily Hunter, Field Book Project

Portrait of Silberglied with a camera, photographer unknown, July 1971. SIA RU7316, Box 17, Folder 11. SIA2012-7948.

In a recent blog post on entomologist Robert E. Silberglied, I touched on the creativity evident in Silberglied’s mixed-media field books. In addition to all of the graphs, sketches, maps, and textual entries, were a plethora of photographic prints and negatives. Some of the images were clearly intended as quick documentation. Others, like the photograph of the butterfly below, are quite beautiful. Was there anything Silberglied couldn’t do?

Photograph of Anartia jatrophae (Nymphalidae) in the midst of expanding its wings after exiting the pupa, the remains of which can be seen next to the butterfly. Robert E. Silberglied, undated (circa 1970s). SIA RU7316, Box 17, Folder 5. SIA2012-7947.

Photography and cinematography were integral to Silberglied’s scientific investigations for two main reasons:

1. Photography allowed Silberglied to document his field work and experiments with butterflies. Still photographs taken in quick succession could freeze butterflies mid-flight (or mid-courtship). Silberglied could then study those fleeting moments.

2. Photography (and cinematography) allowed Silberglied to capture ultraviolet (UV) information otherwise invisible to the human eye. In other words, he attempted to see what a butterfly sees.

A major part of Silberglied’s work with butterflies, was on UV reflectance. I felt completely lost on this topic, until coming across a small field book (Costa Rica, 1972) with what looks like a handwritten presentation that Silberglied gave on “UV Colors in Butterflies.” The draft (written in pen with many cross-outs and corrections) is eloquent and interesting, and most importantly, understandable! Somehow, Silberglied was able to communicate to me (a total novice) an extremely complex concept. In it, Silberglied describes the differences between human and insect vision. UV patterns that are invisible to the human eye assist butterflies with camouflage, finding nectar in a flower, communicating, and attracting a mate. Silberglied became fascinated with translating the invisible UV patterns to human visible images—via photography and cinematography.

On March 2, 1972, Silberglied wrote a letter to the Eastman Kodak Company, asking for recommendations for ultraviolet films. He explains,

I am presently designing a device for simultaneous color, and 300-400nm ultraviolet, 16mm cinematography of living subjects (mostly flying butterflies, closeup) under natural light…

Silberglied goes on to describe his invention that includes two 35mm lenses that have been attached to 16mm motion picture cameras (one recording color film, the other recording UV).

In a letter dated April 24, 1972, Martin L. Scott of the Eastman Kodak Company replied to Silberglied’s interesting question. He praised Silberglied’s inventiveness stating, “Your project seems well-planned, and your equipment seems well-thought out.” He goes on, “I think perhaps some practical experience is needed next.”

The book is full of things a bit out of my range of expertise including a graph of “diachronic beamsplitter transmission curves” (say what?). Also included are carefully recorded UV exposure data, recording focus, exposure, sequence, fps (frames per second), f-stop, and distances of the color and UV lenses.

Photograph depicting a magnified butterfly wing, undated, by Robert Silberglied. SIA RU7316, Box 16, Folder 15. SIA2012-7946.

Silberglied made fascinating use of photography in his field work, and who knows what he would have accomplished today with the abundance of new imaging technologies, as well as advances in sound recording, molecular techniques, and sophisticated methods of tracking individual butterflies. Of course, we don’t have the capacity to really experience the world as a butterfly does, but Silberglied’s work takes us a step closer.

---

The author would like to thank Annette Aiello for sharing her knowledge and expertise. Annette worked closely with Bob Silbeglied at the Smithsonian Tropical Research Institute before his tragic death and continues to work on Lepidoptera at STRI. Thanks also to David Furth and Robert Robbins in the National Museum of Natural History, Department of Entomology.

More information on butterflies, UV reflectance, and photography, can be found in the following resources:

Folsom, W. (2000). Art and Science of Butterfly Photography. Google Books.

Silberglied, R. Communication in the Ultraviolet. Annual Review of Ecology and Systematics , Vol. 10, (1979), pp. 373-398. http://www.jstor.org/stable/2096797

Comments

[Tran]

Thanks for sharing!

I really enjoy these posts, very informative and very unique.