High voltage flash trigger circuit of the Maxxum 7D.
The BCR5AS device is a 600volt 5 Amp TRIAC.
Looks like previous to this there is a transistor oscillator and a step up transformer or coil.
I'll draw up a schematic for this circuit as it converts a logic level signal to a HV switch.
Main camera on/off switch contacts are on the flex board to the right of the PC connector.