Plaster line

An imaginary line across the stage at the back edge of the proscenium arch. Designers measure the whole set from it.

DesignersCrew

Centre lineAn imaginary line from the front of the stage to the back that splits it into two equal halves. Paired with the plaster line for measuring.
ProsceniumA stage framed like a picture, with the audience all on one side looking through an arch.
Ground planA to-scale drawing of the set seen from directly above. Everyone plans blocking, lights and traffic from it.

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