The other thing you might be subconsciously noticing as "odd" is the varying depth or darkness of the shadows. The lunar surface is only illuminated by direct s

The other thing you might be subconsciously noticing as "odd" is the varying depth or darkness of the shadows. The lunar surface is only illuminated by direct sunlight in an otherwise black sky, so the shadows cast by Aldrin and the lander appear pitch-black. But Aldrin himself is being lit by both direct sunlight and indirect light bouncing off the surface, so the shadowed side of his suit still appears diffusely illuminated. It makes sense when you stop to think about it (and you can fairly easily recreate the phenomenon in a raytracer) but it looks unnatural because we're used to direct sunlight always being accompanied by indirect skylight.