With what we’ve covered so far, we can build a back hole. This one is spinning rapidly with a minimally accruing accretion disk. That makes it a Kerr black hole without jets. It’s modeled after the black hole ‘Gargantua’ in the movie “Interstellar.” We start with the Black hole’s shadow. The Kerr metric shows that light can be captured in stable orbits outside the event horizon. For a rapidly rotating black hole, the orbital volume around the black hole would be significant. This would produce a photon sphere shell incasing the black hole. This black hole has the remnants of an accretion disk that is no longer feeding the black hole.
If the disk were not gravitational lensed, the black hole would have looked like this. (Note that it is brighter on the left where the matter is moving towards the viewer and dimmer on the right where the matter is moving away from the viewer. This is due to relativistic beaming.) But, because of gravitational lensing, the massive amount of light rays emitted from the disk’s top face travel up and over the black hole, and light rays emitted from the disk’s bottom face travel down and under the black hole. This combination gives us the full image of how the black hole would actually look.