hello,
Have you considered the idea of having an Illumination filter as the moon changes throughout the days of the month. rise, set, azimuth possible percentage of illumination through a thin layer of overcast versus a thick layer of overcast. I don't have a scientific number of what that would be, but I can say, with a 500' to a 1000' layer and at during a full moon the overcast does scintillate photons and give illimitation over the landscape. after 2500' not so much anymore. it appears as if the overcast is a large fluorescent light in the sky.

respectfully, just an idea.