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Does larger black holes have a photon sphere that is closer to the horizon then smaller black holes? Would you see more of the back holes in smaller black holes compared to larger ones at the same distance? if so can a large enough black hole be completely hidden behind the gravitational lensing to look like distorted space with no black center?

enter image description here

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    $\begingroup$ for the 3rd image, the background is too homogeneous to distinguish simple image distorsion from a kind of approximative transparency $\endgroup$ – user46925 Jan 9 '16 at 8:44
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    $\begingroup$ To the extent that the differences in the output of simulations (which is what you have here, and it is worth keeping that in mind at all times) tell you any thing, they are telling you about the ratio of the range from observer to hole to the radius of the hole. But there is no dependence on the absolute size of the hole. $\endgroup$ – dmckee Jan 9 '16 at 19:56
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If you measure distance in units of the Schwarzschild radius, then black holes look identical regardless of mass or "size" (as you can verify by inspecting the metric line element).

Therefore the answer is negative: A smaller black hole looks exactly like a big one does from further away. Also, the photon sphere is a shell which completely encloses the horizon of every black hole; when you look at a sky containing a distant black hole, you see the horizon's shadow encircled by a series of infinitely many Einstein rings (although only the first is prominent, and the others are particularly difficult to resolve in numerical simulations). And to argue in which direction the horizon "actually is" you're imposing a Euclidean conception onto curved space-time, which seems a bit meaningless. Where did you take your images from?

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    $\begingroup$ With one exception when 2 super massive black holes merge, the new ring of radiative dust may be broken and discretized. $\endgroup$ – user46925 Jan 9 '16 at 8:45

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