So no tripods allowed. Fast prime rather than a zoom? I am in a group, timed entrance, so no time to dally. On the move, 20:00 hours for 40 minutes in December, outdoors. Lighting is by projector. Candles, fairy lights, coloured gels on flood lights. Water reflections, trees and walkways. Any advice, probably no time to change a lens in the dark, a one time opportunity.