What happens if you attempt to operate a Sony SLT (pellicle mirror) camera with the mirror up? Does the camera detect this condition? Will the camera shoot? What happens to autofocus--can the camera fall back to contrast detection? Is the increase in exposure value accounted for?
The SLT-A55 at least no longer focuses but everything works, even with the mirror removed which you can do without too much difficulty. Exposure is off by about 1/3 EV.