Astro Camera
night-by-night colour sweeps and stacks with a camera facing north and towards the pole and zenith
astrocam v3
brightness curves (and an old reference) for a week. Clouds are bright in the suburbs and overcast is about 8, deep darkness about 4. 4 stops or bits is 16x more photons. The pedestal is 6 bits and must be greater than the electrical noise of the sensor.
