Should the dish be shot in an empty room or during service, as a still and a clip?

Yes, on the pass, when the dish leaves as it is served, and the still and the clip are made there. An empty dining room does not improve the dish, and do not stop the whole room for the clip. Pick a gap on the pass and do not book the morning with the venue closed if the dish only exists in service. In the sierra the dish is filmed in an empty dining room and the portion is not Saturday's. Still and clip come from the service dish, without emptying the room.