a stream calibration arrangement for visually determining the position and orientation of a sprayed material stream . use of a stream calibration fixture to determine adjustments to an adjustable spray gun mount to realign a spray stream without altering the taught path of a robot carrying the spray gun . alternatively , the stream is realigned by altering the taught robot path and requiring no gun mount adjustment . stream realignment is also carried out automatically with and without gun mount adjustments . machine vision is used for automatic stream realignment .