People ask me how to become a good interpreter of photographs. Well, there are lots of mathematical techniques we can use to make the data more comprehensible. But the best advice is simply to pay very close attention to the world around you, especially when nothing exciting is happening. Too many people want to limit their observations of the world to momentous occurrences or mysterious circumstances. A proper understanding comes from trying to explain the mundane and disinteresting.
For example, just looking up from my computer screen, I see a peculiar shadow cast on the wall by the edge of the television. It's a multiple shadow with the inset shadow having a sharp edge. Now I know from study and experience that fuzzy shadows are cast by wide area light sources, and sharp-edged shadows are caused by more localized "point" sources. But now I want to know exactly what light sources behind me are causing this. The "point" light source turns out to be a splash of sunlight on the dining room wall. The softer light source is simply the diffuse interreflection of sunlight on the white walls. And I actually ended up being a little surprised because the "point" light source was actually broader in subtended angle (as seen from the edge of the TV) than inferred from the shadow.
Similarly there's a peculiar glow on the walls and ceiling. It's sun reflecting off the hardwood floor. You wouldn't think it would be reflective enough, but it is. These and similar kinds of observations free us from intuition. Or more accurately, they tune our intuition to incorporate more discoverable behaviors of the natural world.
The notion that the lunar environment presents several challenges to perception is paramount. The Moon isn't wholly an alien environment. But just enough to give us pause. John Young famously noted that it was hard to reconcile the sunlit terrain and the black sky. Part of him believed it was night, and part believed day. The attenuation of saturation and contrast with distance was noted by Leonardo in his notebook instructions on painting. It's absent on the Moon. The lunar surface is barren, denying the eye things like vegetation to establish scale with distance. While there is gravity, it's far less than that on Earth, throwing us off balance because the angular rates of falling are too small to notice quickly. Even people who see craters in photos as embossments rather than depressions are exhibiting a million-year-old predilection for believing light always comes from above.
