In Tree Dimensions -- and the inverse relationship between cameras and projectors

Back in June I went into the woods with a projector and a bunch of equipment to build an art piece.  It was a part of the Electric Sky Art Camp, a yearly art event in Skykomish Washington, a tiny town in the middle of the Cascade Mountains (pop ~200).

The piece was called "In Tree Dimensions", and it worked by leveraging how cameras and projectors work in tandem with each other.  The main idea is that there's a tree surrounded by phantom lights.  The brightness and location of these lights are controlled by a MIDI controller.

Here's some footage of the project.  My good camera broke in transit, so unfortunately the best documentation I have is this (heavily corrected) footage from my cell phone.

Dials 1 - 3 move lights around the left side, bottom, and right side of the tree.  Dials 4-5 rotate stationary lights.  Dial 6 looks like a car is passing through.  Dials 7-8 emulate Christmas lights that are strung on individual branches.

A bit about cameras and projectors

Before I get into how this particular project works, I first want to cover an interesting note about cameras and projectors.  Cameras and projectors do opposite things.  Cameras eat 3d spaces and leave behind film.  Projectors eat film and push it back out onto any surface it encounters in a 3d environment (of course, we usually try to project onto flat surfaces).

What's significant about the opposite nature of these devices is that when they are perfectly matched with one another, you get fantastically weird results.  I've experimented with this in past projects:

The effects on this cake were made with a projector (not my work, found on  giphy )

The effects on this cake were made with a projector (not my work, found on giphy)

Related to all of this is a thing called projection mapping.  This is where people project compelling illusions onto the surface of 3d objects.  You've probably seen examples -- usually it's projecting onto buildings.

Almost all projection mapping uses techniques that rely on the relationship between cameras and projectors -- though in these cases, the cameras are virtual cameras in virtual 3d environments.  Use the camera to take footage of a virtual environment, and project it out onto an environment that geometrically identical to the virtual environment.  With some clever programming, this is a fast way to produce some really stunning effects.

Theory behind how "In Tree Dimensions" works

Information flows from tree, to camera, to footage, to projector, back out to tree.

Information flows from tree, to camera, to footage, to projector, back out to tree.

So, I was going into this art event with a different plan.  I was under a tight deadline, and I couldn't afford to spend time constructing a digital 3d model of a tree I found in the woods, so I went with a more analogue hacky approach.  Instead of using a virtual camera, I used a real world camera.

So first, I recorded a tree under various lighting conditions.  To create these conditions, I simply pointed a work light at the tree and moved it around.  Then, I piped the footage back out onto the tree with a projector.  I programmed a MIDI controller so that it would be able to manipulate the footage, giving visitors the ability to replay and scrub through the past on a physical 3d object.

The devil is in the details...

Of course, pure theory only takes you so far, and if you want the project to look good, you have to do lots of clean up work in the process.

I couldn't just project the raw footage back out because of differences in optics between the camera and projector.  Also, to make sure the colors popped and looked good, I had to do some image enhancement.  This video quickly demonstrates what was done to the footage to make it ready to be projected.

Another example of where pure theory failed to help was when working conditions are just awful.  Like, working until 2am in the rain, cowering under a tarp that protected me and my gear from water damage, and improvising a camera situation because my good camera was broken in transit.  "Pure theory" doesn't really help you when the nearest Radioshack is a 2 hr drive away.

But fortunately for me, I was surrounded by an amazing community of new media artists from the greater Seattle area.  As you can see from this photo, I'm just elated and having an amazing time.  Everyone was super chill, super positive, and always willing to help.  And on top of all of this, they were crazy talented and the quality of their work kept me on my game, so I was especially lucky because I just moved out here from NYC and I just happened to stumble upon a cool crowd.

So a big thanks goes out to all of them for keeping my spirits up in these kinda stupid working conditions.  Also, thanks to the Electric Sky Retreat for hosting it and for giving me the opportunity to explore some of my work.  I definitely plan on building another project next year for this event.