This image from Wikipedia shows how a black hole would look like:
A black circle that acts as a gravitational lens for light rays coming from behind.
How would a rotating black hole look like? How would it look like when viewed from side and when viewed from the top (along its axis of rotation)? If I understand it correctly, withing the ergosphere photons are dragged in the direction of the rotation, and just outside it photons would be still heavily influenced by the rotation.
Also this video descibes in detail how would it be to descend into a black hole. What would be different when descending into a rotating one? In particular, what would we see inside the ergosphere? And how would it be different below the event horizon?
