Digitize your old slides with a modern DSLR camera

Until the proliferation of digital photography, film slides were a common way to share photos. After a great vacation in the 70s, you could take your rolls of film for development and have the option of receiving a set of slides. You could then gather all your friends in your living room, place those slides in a projector carousel, and force everyone to stare at blurry images of palm trees projected onto the wall. If you still have a collection of slides (or inherited your parents' collection), this video by Scott Lawrence shows a method for converting them into digital photos.

This approach may seem rudimentary, but it is quite effective. If you look at it from a high level, it's basically taking pictures of the slides with a modern DSLR camera. But these cameras are capable of capturing very high quality images and this process is easy to automate. The key to this automation is the use of a vintage slide carousel. They are affordable and easy to control with a microcontroller, making them perfect for this application.

In this case, Lawrence used an Arduino Leonardo board. It controls two things: the slide carousel and the camera shutter. The user interface, consisting of a six-digit seven-segment display and a rotary encoder, allows the operator to configure the number of slides to capture, pause between slides, backlight brightness, and more. When activated, the controller tells the carousel to load a slide, triggers the camera shutter, and then repeats with the next slide. Each slide only takes a few seconds to load and capture, which means it can scan over a thousand slides per hour.