I looked at my computer screen with all the other lights off. It's tough to see the screen in the second photo I took, so I used Darktable to make the contrast in that photo very apparent.
And here is what the lights in the greenhouse look like.
Also, if you think the paper looks wet, you're right! In order to make my pinhole camera work better, it helped to dampen the paper so that it would be more translucent.