The average color of the New York City sky, updated every 5 minutes.
A clever idea, however his data source is irrevocably corrupted by the auto exposure and auto white balance of his webcam. The result is, sadly, more influenced by the algorithms in his camera than the sky itself.<p>Notice how there's some outrageous and short-lived tones during sunrise and sunset -- that's the white balance jumping around (Possibly an automatic saturation gain too?)<p>Then notice how the brightness doesn't peak and fall during the day, instead jumping quickly from darkness to "full" brightness with frequent dramatic shifts far greater than reality would allow. That's because the moving cloud cover is triggering the auto exposure to jump around incessantly.<p>The ideal fix would be to replace the webcam with a digital camera capable of tethered shooting and fully manual operation. You'd fix the shutter, aperture and ISO values to a level that minimizes clipping, set the white balance to daylight, and point the camera in a direction least likely to be in the sun's path (in the southern hemisphere, that's south).<p>In order to capture the dynamic range fully, you could allow the camera to automatically choose the shutter speed, then compensate in the algorithm by reading the shutter speed from the EXIF data.<p>That said, full points for the idea, and for a great web app to visualize the data!