The Null Program
A null program opens and immediately closes; there are no steps to follow, nothing to do. Light Pattern produces the null program with a NOP instruction ("no op" for "no operation”). NOP is this sequence:
012 -> shorter shutter speed, same aperture,
next color (Red to Green to Blue, back to Red)
The content of the Null Program is as close to nothing as one can get and still follow these rules. They are created by shooting a light source (like a monitor) set as purely as possible to the right color. Although only two photos are needed, a longer sequence can be used with the same result, as long as it continues the 012 pattern.
Light Pattern skips images that have the same amount of red, green, and blue -- it doesn’t know how to read them –- so it skips all-white or all-black images. The Null Program starts with an image overexposed to the point that it’s all white. It cycles through the colors and runs the list of all the shutter speeds that allow a color to register, until it arrives at all black, ending on an image that is again without content for the compiler.