Image above: The bean studio right before photography stopped today.

There is some wonderfully diverse and geographically dispersed development happening on Public Lab’s infrared camera tool. A goal is to improve on the current version, which is just a pair of Powershot cameras, by incorporating a tiny computer which can automatically combine information from two photos (normal color and infrared) and produce finished multispectral images (e.g., NRG or NDVI). These images can document the health of plants, so the tool will be useful to earthbound gardeners and farmers as well as kite and balloon mappers.

One concept is to use a single camera and move a filter back and forth so a pair of color and infrared photos can be taken in rapid succession. Another is to use two tiny cameras (one normal color, one infrared) and put them close together so the simultaneous photos taken have little parallax error. An emergent capability of either design is that close-up photos of plants will be possible. Also, if a computer controls the camera(s), it will be possible to take long series of photos at regular intervals to make timelapse movies. The research group became excited about the potential to make close-up timelapse videos of plants growing in false color infrared or NDVI, and three of us started collecting seeds and potting soil. I have not seen any good previous examples of this type of multispectral video, so it might be an important advance.

Although I did not have a prototype which could make multispectral timelapse videos, I decided to make an old fashioned color timelapse video of bean seeds sprouting. The video is composed of 4400 photographs taken with a cheap webcam connected to a laptop computer. Photography was controlled by a freeware program from TNLSoftSolutions.com. The first day it took 475 photos, one every three minutes, and then for the next two weeks it took a photo every five minutes. Each photo became a single frame and the video has 30 frames per second. So the 15 day video lasts two minutes and 28 seconds. It really doesn't have much to do with the infrared camera, but it’s a fun video.