White pixels represent parts of the image which are lighter than the previous, black pixels represent parts of the image darker than the previous. Unchanged pixels are shown as grey. The difference value indicates the total change from the previous frame. The difference image helps show very faint clouds which are otherwise difficult to see.
Clouds can be detected by using the red/blue pixel value ratio. As clouds appear white or grey, the red and blue values will be roughly equal, whereas clear sky has a much higher blue level. In the above cloud map, pixels with a red/blue ratio of greater than 0.84 are white, and those with a lower ratio are coloured blue.
Brightness: 67.1% (Very High) Exposure time: 1.9 ms (Very low)
The normal image from the camera. The brightness value is the natural logarithm of the average brightness across the sky.
Sun Alt.: 40.1° (Very High)
Moon Alt.: -48.0° (Very low)
Moon Phase: 95.2% (Very High)
Moon Brightness: 0% (Very low)
Exposure time (milliseconds)