Which unit is best to use, and why, when determining how many times easier it is to read a newspaper (or any other printed text) on the moons surface at night under a full earth, compared with reading it outdoors on earth during a cloudless full moon night: Albedo, Bond Albedo, Apparent Brightness, Apparent Magnitude, Geometric Albedo, Lux, or something else?
Albedo is the fraction of light that is reflected. A mirror has an albedo of nearly 1, but a tiny mirror at a distance of 400000km won't do much.
Similarly bond albedoor geometric albedo: this is a statement about the colour of the object, and doesn't directly correspond to brightness.
Apparent magnitude and Apparent brightness are different ways of measuring the same thing. Apparent magnitude is a logarithmic scale, that better matches how our eyes work. These measure how bright the object is in the sky
Lux is a measure of how much light there is at the surface, per square meter. If you want to define reading light, this is the easiest. But it is not a property of the object, it is measured at surface level.
For example, the sun has a magnitude of -27 and illuminates the ground at 100000 lux. The moon has a magnitude of -12 and illuminates the ground at less than 0.1 lux.
Readability requires taking into account the sensitivity of the human eye to various wavelength. This is called Illuminance.
Quoting that, different light sources have roughly these values:
Source Lux Full daylight 10,000 Overcast day 1,000 Very dark day 100 Twilight 10 Deep twilight 1 Full moon 0.1 Quarter moon 0.01 Starlight 0.001