Initial Idea

Background

A large portion of my studio (know as The Hideout) is basically a museum of obsolete technology. I have a collection of all kinds of media archaeological artifacts: TVs, radios, 8mm projectors and film, different types of stereoscopic cameras and viewers, magic lanterns, optical toys etc. One of the things that I’m most interested in is the history of projection technologies and optical illusions.

For a long time now, I have wanted to experiment with combining the old technology from laterna magica (magic lanterns) with the possibilities that digital fabrication offers to the table. Many magic lantern shows used mechanically moving slides and fading between different slides to create the illusion of moving images or simple animations.

What would I like to make

I want to create an experimental magic lantern that uses the lenses from an old laterna magica but otherwise is completely fabricated at the Fab Lab. I will also create various moving or animated slides that use all the different tools and techniques covered during the Fab Academy.

The Lantern

The device itself is not very complicated. It’s essentially just a box with a very bright lamp and a way to mount the lens on it. Below is an example of a real magic lantern.

From Wikimedia

Things I need to consider in the construction:

• What kind of light source to use? I am currently looking into 100W LED lights
• How to power this powerful LED?
• How to have adequate cooling/thermal control for the LED?
• What material should it be?
• How to make it look amazing?

There is one unique difference to normal magic lanterns. That is that I want to develop a system where the projector is able to control or communicate with the slide. Either for direct control of the slide by the operator of the lantern or for creating some automations. This control port between the slide and the lantern should also provide power for the slide.

Things I need to consider in the overall system:

• How to communicate between the slides and the lantern? I’m pretty much decided already on I2C, but I think in addition to the standard I2C (GND,VCC,SDA,SCL), I probably also need to pass higher voltage to the slide for powering motors, electromagnets etc.
• I’m currently thinking of having magnets as the connection port between the slide and the lantern, this way I could make it polarized and reduce the chance of someone putting the slide there the wrong way.
• Is there going to be some standard controls for all slides, such as potentiometers or buttons for speed control or start/stop, that could/should be added to the lantern itself?

At first, I was planning to use old lenses from a real magic lantern, but as I was researching this, I came across this video:

The video explains how to build a DIY projector using fresnel lenses, 100W LED, large format camera lens, partly broken mobile phone, and other components. This got me thinking that I could actually make my own lens assembly instead of trying to find a fully working old one that I would not feel bad about repurposing. Additionally, this inspired me to think about ways to make a projector that is able to show both antique magic lantern slides as well as Netflix.

The slides

The actual slides are going to be more interesting. There I can really experiment with all kinds of possibilities

Ideas for slides I want to develop:

• UV printing on transparent acrylic slides to re-create many of the mechanical slides from original magic lanterns. (Chromatropes)
• Ferrofluid slides where I can basically create projected shadows controlled by electromagnets (This idea is what got me started on this many years ago already. I just never had the time to actually make something.)
• Engraving patterns on the slides with the laser cutter. These types of slides could also work as stand-alone pieces.
• Mechanical rotating slides (like the original chromatropes) but with small motors instead of manually cranking them.
• Using nitinol/flexinol wire to create movement in the slides without motors.
• A digital slide with a transparent LCD screen and an emebedded Raspberry Pi media server.
• A digital slide that runs an emulator of some gaming console on a microcontroller and a transparent LCD screen. Something like this NES emulator for ESP32.

Where to start? Chromatropes

As the first step, I am going to start developing a version of the chromatrope slides. They are mechanical magic lantern slides that have two rotating glass slides. Each slide has a geometric or decorative pattern and the two slides are essentially mirror images of each other. The slides rotate in opposite directions and create these very psychedelic patterns. Here is a short demonstration from one of the chromatopes in my collection.

Here is a visualization of how Chromatrope slides work. Essentially, you just have two slides that are rotating in opposite directions. The slides are also usually flipped copies of each other. The example below is a scan of a real magic lantern slide from the 1800s.

Run the sketch and move your mouse around so that the slides align.

Who will use this?

The lantern will be used by me for audiovisual performances, it will most likely also be used by a friend of mine who does contemporary circus performances and shares my love for magic lanterns and the history of moving image. Part of the project can also work as an interactive artwork in an exhibition.