Conservators wield some impressive photo-processing skills, in no small part because of the extensive photographic documentation we do in our work. We use our image-processing skills for research purposes, too.
Right now I’m taking multispectral photos of limestone funerary stelae from the Roman Egyptian city of Terenouthis so that I can begin to characterize the pigments that were used to paint them. Pigments reflect, absorb, and/or luminesce ultraviolet, visible, and infrared light in characteristic ways, but capturing a good image of these photo-chemical responses can be challenging.
Happy fall from the Kelsey Conservation Lab! In celebration of my favorite season, Suzanne and I bring you this gem from our conservation image archive: multispectral CANDY CORN! Here in the Conservation Lab we use multispectral imaging (MSI) primarily for research. MSI involves illuminating artifacts with ultraviolet, visible, and infrared light, and then capturing the results in an image. Some ancient pigments and dyes reflect and emit light in characteristic ways, and MSI can be used to identify them. We also occasionally deploy MSI for the sheer fun of it — because who wouldn’t want to see what their favorite corn syrup-infused Halloween candy looks like under ultraviolet light?
The image above presents candy corn four ways. Starting at the upper left, the first is in visible light (VIS), or how you’d expect your candy corn to look in a glass dish on your coffee table. Below that we have longwave ultraviolet light (UVL), which causes the candies’ ingredients — possibly the food dyes — to fluoresce different colors. (Cool! And slightly disturbing?) The black-and-white image at the upper right (IRR) shows the candy in infrared light, revealing that candy corn is pretty darn good at reflecting infrared radiation. (Who knew?) And finally we have an infrared false color image (IRR-FC), which transforms the infrared reflectance into distinct colors. This is a post-photo capture process that can help ID pigments, and could tell us something about the food dyes if only we had a multispectral database of such things. (A girl can dream ….)
I for one will continue to consume candy corn in spite of all this information, because nostalgia is a powerful thing, my friends. Thanks for tuning in to our blogroll, and many thanks to former graduate intern Janelle Batkin-Hall for capturing these inspired multispectral candy corn images.