A crane comprising: a lower works having one or more ground engaging elements; an upper works connected to the lower works, the upper works having a boom; characterized by a system for determining a crane status, the system comprising: a sensor assembly positioned to have a line of sight along at least a portion of a length of the boom, the sensor assembly configured to detect light transmission and output sensor information, wherein the sensor assembly comprises a transmitter positioned on the boom and configured to emit a laser beam and a receiver positioned on the boom and having an array of photosensors configured to detect the laser beam, such that the laser beam moves with respect to the receiver vertically as the boom deflects vertically, and the laser beam moves with respect to the receiver horizontally as the boom deflects horizontally, and wherein the sensor information includes information regarding detection of the laser beam by a photosensor of the array of photosensors and information regarding the photosensor detecting the laser beam; and a computer configured to receive the sensor information and determine the crane status based on the sensor information, wherein the computer determines a position of the laser beam on the receiver based on the sensor information, wherein the determined crane status includes: vertical boom deflection and side boom deflection. a lower works having one or more ground engaging elements; an upper works connected to the lower works, the upper works having a boom; characterized by a system for determining a crane status, the system comprising: a sensor assembly positioned to have a line of sight along at least a portion of a length of the boom, the sensor assembly configured to detect light transmission and output sensor information, wherein the sensor assembly comprises a transmitter positioned on the boom and configured to emit a laser beam and a receiver positioned on the boom and having an array of photosensors configured to detect the laser beam, such that the laser beam moves with respect to the receiver vertically as the boom deflects vertically, and the laser beam moves with respect to the receiver horizontally as the boom deflects horizontally, and wherein the sensor information includes information regarding detection of the laser beam by a photosensor of the array of photosensors and information regarding the photosensor detecting the laser beam; and a computer configured to receive the sensor information and determine the crane status based on the sensor information, wherein the computer determines a position of the laser beam on the receiver based on the sensor information, wherein the determined crane status includes: vertical boom deflection and side boom deflection. a sensor assembly positioned to have a line of sight along at least a portion of a length of the boom, the sensor assembly configured to detect light transmission and output sensor information, wherein the sensor assembly comprises a transmitter positioned on the boom and configured to emit a laser beam and a receiver positioned on the boom and having an array of photosensors configured to detect the laser beam, such that the laser beam moves with respect to the receiver vertically as the boom deflects vertically, and the laser beam moves with respect to the receiver horizontally as the boom deflects horizontally, and wherein the sensor information includes information regarding detection of the laser beam by a photosensor of the array of photosensors and information regarding the photosensor detecting the laser beam; and a computer configured to receive the sensor information and determine the crane status based on the sensor information, wherein the computer determines a position of the laser beam on the receiver based on the sensor information, wherein the determined crane status includes: vertical boom deflection and side boom deflection.