PHOTOS: Magic Lantern projection slides

Posted on March 20, 2019

Here’s something interesting: Digital projectors appeared in engineering classrooms here at Queen’s in the early-to-mid-2000s. Prior that, from the 1950s, instructors who wanted something more visual than just a chalkboard used overhead and 35mm film slide projectors. Before that, from as early as the 1850s, the high-tech teaching aid for lecturers was a photo-projection standard called Magic Lantern. Developed when photography was still new technology, it used a concave mirror and a simple lens to project light (from candles in the beginning) through fragile, one-of-a-kind, 3 ½- by 4-inch glass slides.

A small collection of those slides have been sitting on dusty shelves in the Department of Electrical Engineering here at Queen’s probably since at least the 1940s, likely even earlier than that. They, and the wooden box they live in, are mostly beautifully hand-made. The resolution of the images on these slides is much higher than consumer digital technology allows for today. The images seem to be mostly of really large electrical components used in early electrical power generating and transmission systems. Thanks to ECE Computing Technologist, Steve Humphrey for sharing them.