Photographic slides were popular in the middle part of the 20th century, but are long forgotten now. If you’ve found a handful in a dusty attic, you might consider sending them away to be digitized professionally, or using a flatbed scanner at home. [Bryan Howard] found himself with over 200,000 slides, however, so that just wouldn’t do. Instead, he endeavored to build an automated scanner of his own.
Like many similar projects, [Bryan] started with an existing slide projector as a base. This means that all the difficult work of slide transport is already taken care of. The projector has then been upgraded with an LED light source and other tweaks befitting its new role. An Arduino Pro Micro runs the show, firing off the camera to image each slide before loading the next one into place. The DSLR responsible for imaging is then hooked up to a PC so the incoming images can be checked while the machine is in operation.
Preliminary tests are promising, with the scanner successfully capturing several slides in a row. [Bryan] estimates that, with a capture time of between 1 and 2 seconds per slide, it should take somewhere between 2-5 days to image the entire collection.
We wish [Bryan] the best of luck with the project, and look forward to seeing the final results. We’ve seen similar work before, too. Video after the break.
Continue reading “A High-Speed Slide Scanner Build”
The Cairo hackerspace needed a projector for a few presentations during their Internet of Things build night, and of course Friday movie night. They couldn’t afford a real projector, but these are hackers. Of course they’ll be able to come up with something. They did. They found an old slide projector made in West Germany and turned it into something capable of displaying video.
The projector in question was a DIA projector that was at least forty years old. They found it during a trip to the Egyptian second-hand market. Other than the projector, the only other required parts were a 2.5″ TFT display from Adafruit and a Nokia smartphone.
All LCDs are actually transparent, and if you’ve ever had to deal with a display with a broken backlight, you’ll quickly realize that any backlight will work, like the one found in a slide projector. By carefully removing the back cover of the display, the folks at the Cairo hackerspace were able to get a small NTSC display that would easily fit inside their projector.
After that, it was simply a matter of putting the LCD inside the display, getting the focus right, and mounting everything securely. The presentations and movie night were saved, all from a scrap heap challenge.
Who hasn’t thought about turning a 1950s slide projector into a digital projector? [Matt] did, but unlike most of us, he actually did it.
[Matt]’s friend [Angus] found an old, single-slide, sans-carousel slide projector in the trash. It’s a wonderful piece of ancient technology with a fabric insulated power cord and bakelite lamp socket. This projector was upcycled to the 21st century by adding a 10 Watt LED and a Nokia 1200 LCD.
For the electronics, [Matt] used an ATmega88 microcontroller. There’s an infrared receiver so the remote from an in-car CD player can be used to advance the slides and turn the projector on and off. The LCD is controlled by a bit of bit-banging from the Mega88, using hard-coded images of Che Guevara, Hendrix, Space Invaders and some old-school Macintosh/Lisa icons. Unlike the screen printed t-shirts at American Apparel, Che is the only authentic image in this project; this projector might have been made after Guevara came to prominence.
With a 10 Watt LED, it’s not the brightest projector on the planet and the picture is a little washed out in a bright room. With dim lighting, it’s a very good project even if the images are static.