I’ve wondered why images taken by the Hubble Space Telescope-like the famous 1995 image of the Eagle Nebula-have an odd, stair step cropping:
Credit: NASA, ESA, STScI, J. Hester and P. Scowen (Arizona State University)
It’s because of the design of the instrument used for these shots, the Wide Field and Planetary camera. It actually has four cameras and the upper right camera takes a more detailed image.