WALL
EYE
Build your own
opaque projector.
By Steve Lodefink
Magnify and project
artwork in books and
computer printouts.
What’s an opaque projector? You know, one of those contraptions that takes
flat, reflective subjects such as printed pages, leaves, or coins, and projects
them onto a screen or wall. Opaque projectors were common classroom
presentation tools during most of the 20th century.
Although made largely obsolete by the use of find one of the majestic 1,000-watt giants from
video cameras coupled to video displays, opaque yesteryear at a swap meet, then consider yourself
projectors are still being made and sold. Marketed charmed. I was not so lucky.
today mainly to art students and hobbyists for use While searching for a projector to buy, I did hap-as drawing enlargers, entry-level models tend to be pen upon a free PDF download of an old Edmund
dim little plastic toys that can only accommodate Scientific DIY booklet called “How to Build Opaque
puny 3" or 4" originals, and have to be used in a Projectors.” Just 20 pages long, the pamphlet is
totally darkened room due to their small apertures packed full of projector theory, useful tables and
and weak light sources. If you’re lucky enough to formulas, design considerations, lighting and lens
Photograph by Robyn Twomey
74 Make: Volume 14
