What could explain the dark bands seen in these pictures?
This photo was taken at the Harvard Museum of Natural History, using a Pixel phone. The picture is shot looking through a glass panel into a geology exhibit that has white illumination inside. There is also white room light outside the glass panel. The bands were aligned vertical relative to the phone, and decreased in contrast when taking the photo from farther away.
Here is another picture into the neighboring glass-covered exhibit, showing the vertical bands in different position and with different contrast to illustrate the effect:
Pictures from more than 1 meter away from the glass panel didn't show the dark bands: