black hole entropy

kurious

If a large number of pions decay into photon pairs which travel in opposite directions, and one member of each pair travels to a fixed point in space,
a black hole would form at the fixed point in space.Since the photon polarizations are coupled, I could get information about the microstates in the black hole
by measuring the polarization angles of the photons that are outside the black hole.
And by placing a number of polarizing filters in a line, for each photon travelling outside the black hole, with one photomultiplier per photon to detect each photon, I could gain information on the microstates in the black hole at different periods in time.So I would know more about a black hole than just its total spin,mass and charge.But would this technique work for black holes that are not formed from large numbers of photons emitted by pions?