Fractal Projection Art

(Submitted by daniel on August 14, 2013)

This summer, a friend invited me to participate in a 10-person joint art exhibit at Art Plaza, Oita. I could have an entire room to myself, and was told that I could try any type of experimental art I liked within the space. I used this as an excuse to try something I've wanted to do for years, which is to make fractals using only projectors and a camera (no computer). The following is a compilation of videos from my exhibit, as well as some footage taken of a collaboration with Joanne Yoshida's yoga dance class.

Everyone from children to grandparents got to try their hand at creating 'fractal art' out of light. This is a compilation of some of the interesting things people made.

YouTube video (9m 43s)

All credit for the idea goes to Matt Bell, who I believe was the first person to ever record and share the process in 2008. Watch his YouTube video to see my inspiration for this project. Read on to learn more about why this fractal phenomenon happens and how you can recreate it yourself!

Fractals are typically created on a computer using an equation or set of rules which determine shape and color. A common trait of most fractals is their tendency to be self-similar, made up of smaller copies of the entire object. Similar shapes can be seen in plant and animal systems, such as a nautilus shell, fern frond or tree limb. Here is an example of a simple fractal.

By connecting multiple projectors to a video camera, then pointing the camera at the projection, you can essentially recreate the self-replicating system used to create these fractals, as the camera continuously copies its own output 60x a second. The resulting images can be startlingly beautiful, and due to the number of variables involved in the system (position and rotation of each projector, as well as the camera), there is an enormous variety of images that can be created. It is, in fact, very difficult to generate the same image again after moving any of the projectors. Below is an image of a structure similar to the fern above.

The bare minimum required to create the complex, space-filling patterns seen in my video would be a camera, video splitter, and 3 projectors. Adding a fourth projector, however, allows for much more detail, and makes it easier to fill a wall with light. My setup contained the following:

• Canon IXY Digital 700 - Compact digital camera with video-out. Firmware modified with CHDK to remove all text from the video output.
• NK-V-401 - Inexpensive RCA 4-way video splitter
• Panasonic TH-AX100 - Large, bright, home theater projector
• Optoma ML500 - Bright DLP projector
• NEC LT150 - Old, dark projector
• TAXAN PL105S - Small, portable projector

These were connected as follows:

This arrangement worked very well for the space available, but the ideal equipment would include projectors with similar brightness. In my case, the brightest projector had almost 10x the lumens of the darkest, but luckily I was able to adjust the zoom and brightness of the brighter projector to compensate. I should also mention that while the DLP projector had excellent brightness and sharpness in person, its LED-powered image may appear to flicker if you record a video of it, like in my footage. I arranged the projectors to slightly overlap in the following manner:

To achieve this layout reliably, I fixed the projectors to a box with adjustable standoff screws in the mounting points.

This is only one of many MANY possibilities, however. Every change in the position, size, color, brightness and skew of the picture will have an effect on the entire image, and experimenting is the best way to find out what works best. Some things to try include:

• Horizontal and/or vertical flipping of various projectors
• Changing hue/color settings to make some projectors warmer, others cooler
• Put shadow-casting objects (including people!) in front of the projectors
• Add laser pointers or other sources of small, bright light into the view of the camera

In general, having projectors with similar orientation and color settings will create shapes with very defined structure and self-similarity. Changing settings, such as horizontal/vertical flip, or skewing colors, will add organic complexity to the image, which can also be very beautiful. Try everything!

As this exhibit would eventually have hundreds of visitors, I wanted to make it very interactive and easy for people to try their own hand at making some shapes. This is why I settled on a fixed-projector, movable-camera design. I mounted the camera on the end of a smooth dowel rod which can be easily pointed at various parts of the wall, as well as rotated at the same time. The extra length helps to steady the image, which would otherwise be fairly jerky if handheld.

In my experimentation, I managed to burn out a couple handheld cameras, which are not made to stay on for hours at a time. Because of the burnouts, however, I got to try several different devices, which all had their own quirks and ways of dealing with the changing brightness and colors of the fractal images. I found that some cameras are too sensitive to the light changes, and will flash between dark and light constantly, while other cameras may have trouble with auto-gain in the dark areas. Either way, you may need to tweak the projector settings to provide just enough brightness (black level), while not overwhelming the camera and blowing out the image. Again, experimenting is the best way to find out what works. I would simply say that the camera made the biggest difference in the color and quality of the fractal images made, while the type and quality of the projectors only affected the overall brightness and sharpness of the final image.

The art exhibit went better than I could have ever imagined, and I got quite a few people who stayed for half and hour or more just to play with the camera making new fractals. The ability to create beautiful, moving and breathing images instantly using only your hands is something I feel may be unique to fractal projection. The instant feedback allows the viewer to quickly learn how movement translates into shapes and colors, while the endless complexity of the fractal keeps it fresh and new. I can imagine very successful exhibits where a much larger and professional installation of multiple projectors could attract crowds of people eager to create their own one-in-a-quintillion fractal.

If you have any questions about fractal projection, or are interested in trying a collaboration, please do not hesitate to contact me!