Because Multi Camera (and similar devices) simply start sequence acquisitions in all their physical cameras, each physical camera calls PrepareForAcq() (which opens the shutter) and AcqFinished() (which closes the shutter).
Usually opening/closing the shutter is idempotent so there is no issue with opening. For closing, too, most setups will not have an issue because they use cameras that are synchronized in hardware.
But, for example, two unsynchronized cameras should work for Live view, and stopping Live could theoretically result in the shutter starting to close while some of the cameras are still exposing the last frame(s).
Even when the cameras are synchronized and the sequence length is finite, there could be problems if the exposure times are significantly different: the short-exposing camera may "finish" its acquisition and call AcqFinished() before the long-exposing camera finishes its exposure for the same frame.
Because Multi Camera (and similar devices) simply start sequence acquisitions in all their physical cameras, each physical camera calls
PrepareForAcq()(which opens the shutter) andAcqFinished()(which closes the shutter).Usually opening/closing the shutter is idempotent so there is no issue with opening. For closing, too, most setups will not have an issue because they use cameras that are synchronized in hardware.
But, for example, two unsynchronized cameras should work for Live view, and stopping Live could theoretically result in the shutter starting to close while some of the cameras are still exposing the last frame(s).
Even when the cameras are synchronized and the sequence length is finite, there could be problems if the exposure times are significantly different: the short-exposing camera may "finish" its acquisition and call
AcqFinished()before the long-exposing camera finishes its exposure for the same frame.