Engineering, Experiments, Smartly

Nostalgia for Overhead Projectors

overhead projector

Bret Victor gave an entertaining talk on the history and/or future of computing at DBX 2013. In addition to the fascinating subject matter, Bret took the charming step of presenting with transparencies and an overhead projector.

We thought it’d be fun to recreate this effect. An evening of hacking resulted in a new toy: TransparenCSS (demo | source).

We’re abusing -webkit-mask-box-image, so for the full experience you’ll need Safari or Chrome. Firefox works, but you’ll be missing out on the “virtual glaucoma” effect.

Feel free to use TransparenCSS as a base for your own retro-future conference talks.

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†Technically, an overhead projector fitted with a camera in the armature. Presumably, it would have taken a fairly strong bulb to project an image large enough for the entire conference hall…