There are a couple of noticable lighting irregularities in this episode. First, the Olesons supposedly meet the Ingalls at 6:00 in the morning to leave for the camping trip, yet the shadows on the ground are not elongated at all. Clearly, this scene was filmed near noontime. Also, in the scene around the campfire, it's pitch black behind Ma and the girls, but when they cut to Mrs. Oleson and her children, the viewer can see daylight through the trees in the background. Though the two groups are implied to be carrying on two different conversations at once, they clearly weren't filmed simultaneously.