Based on the shadows in/around the craters, the sun appears to be behind the camera. The shadow in the lower left quadrant of the photo appears to be from part of the lander, but what part? The shape looks sort of like a rocket nozzle, but to cast a shadow like this, it would have to be on top of the lander, pointed upward.
From this illustration of the lander, it looks like it could be the upward-pointed thruster on one of the RCS pods…but based on the size of the shadow in that photo, that would mean the camera must be zoomed in pretty tightly. Also, the shadow below the nozzle-shaped shadow doesn’t match what I would expect to see based on the illustration, which shows a pretty substantial base for each array of RCS nozzles.
It’s one of the RCS quads- the picture is likely taken out of the window of the LEM, so it’s in very close.
The Apollo cameras were all fixed focal length medium format Hassleblads- 80mm f2.8 for within the LEM, and another camera with a 60mm f2.8 lens for outside. The outside one had what’s called a “reseau plate” that gives it those little crosses in the grid pattern. They had manual settings for aperture, distance and shutter speed.
All you’re seeing here is that their depth of field is proper for what they’re taking photos of (the ground outside the LEM), and that the RCS quad isn’t within the range of the depth of field- it’s too close-in, so it’s blurry. This is due to the particular combination of aperture and distance set on the camera (we don’t know the actual settings AFAIK, so we can’t calculate the DOF).
With what’s been described so far, and looking at how the LEM was designed, that’s the back of the RCS quad, out of focus because it’s so close, and dark because it’s in the shadow of the hull of the LEM.
That explains why the surface looks so creamy smooth. I suppose if I had followed the link under the photo, I would have found that Maskelyne Crater is 22 km across, realized that photo was taken from orbit, and that the thing I thought was a shadow from the lander couldn’t possibly be a shadow from the lander.
Also, the object is very fuzzy (out of focus) whereas the surface of the moon is in focus, so it can’t be a shadow on the surface (and also the moon can’t be a miniature model just outside the window ;))
Also notice the RCS “shadow” (which is what initially I thought it was too) itself has reflections off of it. Those reflections mostly are on the right half, and due to the location of the light source which appears to be behind and to the right of the camera.
I should clarify, this is certainly not what is happening here, as the distances involved I would expect the shadow to be much, much more diffuse (if at all really visible from that distance.)
