An exposure system includes a light source emitting a beam along an optical axis that is capable of inducing a multi-photon reaction in a resin. The exposure system further includes a resin undergoing multiphoton reaction, as well as an automated system including a monitor that measures at least one property of the beam selected from power, pulse length, shape, divergence, or position in a plane normal to the optical axis. The monitor generates at least one signal indicative of the property of the beam, and a sub-system adjusts the beam in response to the signal from the monitor.