Dark Zone allows astronomers and other researchers to convert a sky brightness value to multiple units of measure, and shows the corresponding dark zone color as defined by the New Atlas of Artificial Sky Brightness (2016, Falchi et al). Sky brightness values may be taken from a device (such as Unihedrons Sky Quality Meter), or it may be a visual estimate.
Enter the brightness value as MPSAS, NELM or Mcdpsm, select the unit of measure, and tap Convert. Values are shown in all supported units, and the zone color is shown.
Units of measure are:
Mpsas = magnitudes per square arcsecond
Nelm = naked eye limiting magnitude
Mcdpsm = millicandelas per square meter