Those are not my figures, those are from the authors of the paper on 'Orbital imagery for planetary exploration'. I am asking what the measured values are, not theoretical ones base on assumptions. It was a trick question really as there are no actual measured values I can find, except one, which was of the Earth from half way to the Moon with a spot meter reading of 320 lumens.Your figures are wrong.
https://youtu.be/x1F4ujSA9Rc?t=528
Does that seem right by your reckoning Higsy?
Its puzzling to me why the light levels on the lunar surface are not well studied. If there are going to be colonies or maybe mining operation on the surface then surely they need to know some basic figures. On the near side it will never be totally dark at night due to Earthshine and NASA determined it would be bright enough for the astronauts to safely conduct their experiments. We can see well enough under a full moon to perform many tasks, and according to NASA Earthshine provides 75 times more photons than does the full moon on Earth so it should be easily possible to work though the lunar nearside night.
What about the other extreme? At mid day on the near side will they need the dark visors or Neutral density filter glasses. Just how bright is it at mid day?
Why don't we know?? And what about the far side? We have no clue whatsoever, though I'd expect the Chinese to have taken a light meter, or knowing the camera specifications and exposure times could work it out.
https://www.bhphotovideo.com/explora/ph ... ty-filtersThe neutral density (ND) filter is one of those tools that should be in almost every photographer’s camera bag.
But NASA doesn't need them on a blindingly bright lunar surface, or to take photos of the Sun from space? Harumph.