An augmented image is generated by capturing a visual image of a site with a digital camera, generating a virtual image or associated information from a digital model of the site, and superimposing the virtual image or associated information on the visual image. To register the digital model with the visual image, a sensor pole is introduced into the field of view, and a combined visual image of the site and an optical target on the sensor pole is captured. The position and orientation of the sensor pole with respect to the site reference frame are measured by sensors mounted on the sensor pole; the position and orientation of the digital camera with respect to the sensor pole are calculated from image analysis of the optical target on the sensor pole; and the position and orientation of the digital camera with respect to the site reference frame are calculated.