This article appeared in Make: Vol. 86. Subscribe for more maker projects and articles!

I learned about the classic stage illusion “Pepper’s Ghost” from an episode of Mr. Wizard’s World on Nickelodeon, sometime in the late 1980s. Many of his household science experiments were small and easy to replicate at home but occasionally Mr. Wizard would show off something really spectacular to his adolescent co-stars. In this particular segment, he produced an apparition of a skeleton onto a chair in a room that definitely did not have a skeleton in it before he cut the lights. He explained how the reflection illusion worked, with a large angled sheet of glass between the empty chair and the opened door. It was amazing, but I knew there was no hope of trying to create that effect at home. Also, where was I going to get a skeleton?

Thirty years later, in 2019, I was watching The Imagineers, a documentary on Disney+ about the history of Disney’s Imagineering department and the development of the theme parks. The early episodes discuss Pepper’s Ghost multiple times, especially in reference to the amazing usage of the effect in the Haunted Mansion attraction. It rekindled an old curiosity and now, as an adult, I realized that I probably had all the supplies needed to make my own Pepper’s Ghost illusion.

So, I slid a piece of framing plexiglass at an angle into an aquarium, plopped an old LCD display on top of the tank facing down, and fired up a video of a goldfish on a black background. It worked great! I was amazed at how easy it was to make a convincing illusion of a swimming fish, so I continued with it. Eventually I tried out the effect with a bell jar on top of my iPad, with a rounded piece of polycarbonate as a reflector. This was the beginning of a whole new journey that led me through the worlds of photography, plastics, synthesizers, and real-time motion graphics.

YouTube player

Suddenly, after twenty-something years as a commercial artist, I was now a budding audio-visual installation artist? I had dabbled with video art but my previous experiments with black-and-white TVs now seemed to make more sense alongside the exploration of Pepper’s Ghost.

It all felt like one big discovery and it all happened right before the pandemic hit. It turned out that I would soon end up having plenty of alone time to experiment.

My thing for televisions

Just about any sort of display can pair well with a Pepper’s Ghost, but I like cathode ray tubes the best. There’s something mesmerizing about the glow of a CRT, especially black-and-white sets from the 1960s and 70s. They have an almost neon intensity that is impossible to reproduce with LCD and other more modern technologies. I have a growing collection of vintage televisions of various sizes, shapes, and ages. There’s everything from a built-like-a-Buick 1958 RCA Sportable to a minuscule 1969 Symphonic Minni portable. I’ve got non-TV CRTs too, like a monitor that was originally used with a black-and-white video camera for microscopy. Mainly, though, I collect 1970s solid-state TVs from brands like Zenith and General Electric; their picture is often very strong, nearly 50 years on, and sometimes they’re fashionable too. Case in point, I have a Zenith Sidekick that’s covered completely in denim to match the blue jean craze of 1974.

Workshop photography by Keith Hammond

I try to avoid opening the back of my TVs whenever possible, so I send video from my computer through a series of adapters that transform the digital signal to an analog format that’s agreeable to my television’s VHF antenna connection. HDMI-to-VHF all-in-one devices do exist but I haven’t tried them out. They seem to be more expensive than a simple HDMI-to-composite adapter/scaler paired with an RF modulator. Remember RF modulators? Well, these days they seem to appear at every thrift store’s electronics section for cheap.

Beyond the adapters, you need cables such as HDMI, composite video (RCA yellow plug), and copper coaxial, and if your TV only has screw terminal connectors you’ll need a matching transformer with coaxial-to-spade connectors. If you’re of a certain age, this can bring back memories of hooking up an Atari 2600. When everything is connected and working, it feels like magic to drag windows from the desktop over to the tube of the television.

Synthesizers, sound, and video

Originally, I was posting my live-video experiments online using sounds from my record collection but I quickly realized I probably shouldn’t be leaning too hard on other people’s music for my own content. I started making original audio with a toy Stylophone, a handheld plastic thing that you control by touching or dragging a metal-tipped pen across a bed of metal keys. It sounds like a drunk chicken. Eventually, I graduated to an updated Stylophone with built-in reverb and some filter controls. Those simple controls were my introduction to the concepts of subtractive synthesis, and I needed to learn more.

There are many options for beginner synthesizers and my first instrument ended up being the Moog Mother-32. I bought it because it seemed well organized and legible, even though I had no idea what anything meant yet. It has vintage looks, absolutely no screen, woodgrain sides, and red blinky lights. Part of my rationale was that even if I couldn’t make it sound good, at least it would look great on camera. Over time, I acquired a Moog Subharmonicon and a DFAM (Drummer From Another Mother) to finish off the three-tier “Sound Studio” set. They each have their own focus and each opens up new possibilities in the others.

As it turns out, synthesizers are sort of addicting and it’s easy to spend loads of time and money on this highly entertaining game of audio logic puzzles (see “Modular Synthesizers,” Make: Volume 85). If you’re interested in trying out the concepts of synthesizers without breaking the bank, I recommend VCV Rack. It’s a sort of analog synthesizer emulation software that has a huge community of developers and users. VCV Rack can receive MIDI from hardware controllers and I use it all the time to output MIDI for controlling other things like video software, such as VDMX.

VDMX is a live-performance video software for Mac, and I use it to manipulate video that I send to my TVs. It’s a peculiar piece of software and also very powerful. The UI seems to have remained in the late 1990s — there’s still no Undo function, and windows float untethered to any sort of overarching framework. To the uninitiated, it might appear outdated, but there are plenty of reasons to push past that impulse, and I’m glad I stuck with it. VDMX can easily integrate system audio and MIDI devices, it has simple options for spanning across multiple displays, and it’s got a modular approach that allows for any slider or button to communicate any other slider or button inside of VDMX. It’s miles to the left from Adobe and I deeply enjoy uncovering its mysteries.

I try to use videos that exist in the public domain for most of my projects. The Prelinger Archive at The Internet Archive has an excellent and extensive collection of videos in the public domain. Originally, I was just trying to find interesting footage that wouldn’t content-match on YouTube but it didn’t take long to become enamored with these time capsules of ephemeral film. There are vintage cigarette advertisements promoting the freshness of one brand over another, cringe-inducing etiquette reels from the 1950s, random cross-country amateur roadtrip films, and corporate promotional films about the latest advances in one technology or another. It’s a deep well of moving images to pull from and also great for sound.

My studio space

Like many people working in San Francisco, my workspace is also my living space. I rent a ground-floor studio apartment with plenty of storage. Admittedly, it’s not the most practical situation for a vintage TV museum / maker space, but I’m working with what I have. There’s a pantry off the kitchen that I’ve repurposed into an art space and it’s currently where I package and ship my enamel pin designs. I use an Intel Mac Mini in the main room to operate VDMX since it seems to be most stable in the pre-Apple silicon world. In the pantry studio, I have a bare-bones M1 Mac Mini for editing and rendering my short social media clips.

I still sometimes draw and paint, so the studio-pantry is also where I leave the mess that I make while doing that.

The living area of the main room is now home to a giant polycarbonate dome atop a 55″ flat-screen TV for Pepper’s Ghost purposes. Originally it was a designer bubble chair that I found among the secondhand couches at Community Thrift. I decided it would be better taking up my space next to my couch instead. My desk is a vintage Steelcase Tanker Desk that was handed down to me from a video editor friend. It had plenty of surface area which I have filled completely with computer and audio gear.

By necessity, the living area is also a photography studio with a few light stands and tripods placed here and there at all times. I shoot with a Canon M6 Mark II sideways on a tripod for capturing vertical video. I use a Ninja V recorder to get the most out of the HDMI feed from the camera. A diffusion filter in combination with an ND filter on the Sigma 16mm lens helps manage the wild brightness from the CRTs and LEDs. Sometimes, I’ll use a vintage Russian lens with an adapter and speed booster to create wider or macro shots.

There is a lot of trial and error with filming Pepper’s Ghost videos. Depending on the screen and the image itself, the environmental lighting needs to be adjusted accordingly. For the effect to be vibrant, it always needs to be a little dark. It’s also important to see the environment around the effect, so it can require a balance of small lighting adjustments. I also use subtle color and lighting post-production adjustments in DaVinci Resolve video editing software to help re-create what the video looks like in-person.

Pepper’s Ghost Illusion — From Dickens to Tupac

Image by Wikimedia Commons

Stage Fright: The famed ghost projection technique was invented by English engineer Henry Dircks in 1858 in an effort to debunk spiritualists and to improve upon their “magic lantern” phantasmagoria shows. Debuted in the theater in 1862 by John Henry Pepper — the two men shared a patent — the illusion soon appeared onstage in The Haunted Man by permission of the author, Charles Dickens.

Fatal Attraction: Board your Doom Buggy to be scare-tained by a gazillion ghosts in Disneyland’s 54-year-old Haunted Mansion ride — most of them still created by animatronic puppets and the Dircks/Pepper illusion.

Photo by Disney
Photo by Gorillaz

Reanimated: Digital natives rediscovered Pepper’s Ghost when the animated avatars of Gorillaz appeared onstage via 3D projection at music awards shows in 2005 and 2006, and again when the late Tupac Shakur performed “live” with Snoop Dogg and Dr. Dre at Coachella in 2012, kicking off a freaky fad for “hologram tours” by artists living, dead, and virtual. —Keith Hammond

Make a mad scientist Pepper’s Ghost Flask

Image by Joshua Ellingson

You don’t need a giant bubble dome to create your own Pepper’s Ghost illusion. It’s a very scalable effect, requiring only simple materials. that are easy to come by. I’ve even made demo videos about how to make a Pepper’s Ghost with a domed coffee lid, snack packaging, and your phone.

Since Halloween is always just around the corner, let’s make a Pepper’s Ghost Chemistry Flask. It will be right at home in a haunted house, mad scientist’s laboratory, or Halloween party.

Project Steps

1. Print the Template Pattern

Download the template file for the reflector and cut it out. This shape will sit inside the flask at an angle to catch the reflection of the image on the display. The shape should match the geometry of the flask so that the plastic isn’t very visible. To get it right, we’ll need to practice on card stock.

Step photography by Joshua Ellingson

2. Cut the Template

Trace the printed template onto the cardstock paper and cut it out. Cardstock is more rigid than printer paper, so it will more closely emulate how the finished reflector will sit inside the flask. It’s also much more visible than transparent plastic, so you’ll be able to understand better how to refine your result.

3. Test-fit in the Flask

Roll up the cardstock cutout and shove it inside the flask. Move it around with tweezers or pliers to position it at something close to a 45° angle. Take note of any bending or other issues with the angle. If the cutout isn’t sitting evenly at an angle, remove it and either trim to fit or start over with a new piece of cardstock. It’s worth it to try a few times if needed.

4. Cut the Reflector

Once you’ve arrived at an acceptable cutout, use it as a template for the clear polycarbonate plastic sheet.

If your plastic has a thin protective overlay, leave that on while tracing your template with permanent marker; that way, you can peel it away with your marks after the cut is complete. Carefully cut out the plastic along your trace with scissors.

5. Roll It Up

This plastic is very flexible; it should roll up like a fruit-snack without creasing or breaking.

6. Shove It In

Wide end first, shove your plastic roll-up into the flask. If everything went correctly, the plastic reflector should pop open into the same position as the cutout template.

7. Choose a Test Video

Before settling on a final subject matter for your Mad Scientist Pepper’s Ghost Chemistry Flask, it’s a good idea to test out what you’ve made so far to ensure that the effect is working. Find a video or image on a black background. Anything black in a Pepper’s Ghost illusion becomes transparent, so the focus of the video will appear to float.

A quick Google search will yield loads of stock video of various creatures and objects against a black background. Find one with bright colors against that very dark or black background, There’s one in particular that I use so often that I paid for an HD version of it, and the goldfish has sort of become my mascot.

8. Test Your Pepper’s Ghost Flask!

Dim the lights and place your prepared flask on top of the video screen. It’s alive!

You might notice that the image is upside down; in that case, just rotate the display so that it’s facing the other direction.

Also remember that anything in the flask will be a mirror image of what it is reflecting. This could be important if you’re thinking of putting text inside the flask. If so, you might use a video editing software to flip the video horizontally so that it reflects correctly.

Conclusion

Now that you have a working Mad Scientist Pepper’s Ghost Chemistry Flask, all that’s left is to elaborate on your creation. What would it look like filled with green liquid? Creatures, spirits, eyeballs, or body parts? Do you have other chemistry glass that could use a floating experiment inside? Would you like to make your own animation?

Animation options

If you’re using an iPad, the popular drawing app Procreate has options for simple animation. It’s easy to make a frame-by-frame animation against a black background and then loop it as an animation inside the flask. If you’re familiar with other motion graphics software like Adobe After Effects then there are loads of possibilities for custom mad scientist creations.

iPad as external display

Sometimes, I use Apple’s Display Preferences to turn my iPad into an external display for my Mac (a feature called Sidecar). Then I use real-time video software VDMX to produce audio-reactive Pepper’s Ghost effects from my iPad’s screen into a glass container. Although it has great MacOS integration, Sidecar can behave unexpectedly when running video software. A great alternative might be the YAM (Yet Another Monitor) app for Mac and iOS. YAM seems to have very low latency and supports iPhone and other devices.

All shapes and sizes

You can use almost any size or shape of glassware or other transparent containers for this project. I’ve used cheap snow globes, and bell jars ranging from gigantic to this tiny one that fits on my TinyTV.

Featured photo by Joshua Ellingson. This article appeared in Make: Vol. 86.