For V100:R2 systems:
For a 12 camera system, a nice camera setup size is about 6m x 6m, mounted about 3m off of the ground. I would recommend arranging the cameras in a square, with 4 in the corners, and the remaining 8 spread evenly on the sides between the corners (putting the cameras roughly 2m apart linearly, if the whole setup area is 6m x 6m).
We're actually working on diagrams at the moment which should better communicate recommended setups.
If you have an S250e system, you should be able to utilize most, if not all, of your room.
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