Tunnel data group visit to Photarc Surveys Ltd. Wetherby (LR-IMS-002)

G. Barker (LM), M.Waters (ER) and G.E. Fletcher (BRR) met R.M. Stanbridge and J.C. Boardman, directors of Photarc. The purpose of the visit was to review Photarc's tunnel profiling procedure, to examine their digitising equipment, and to discuss their proposed stereo comparison technique. In addition, L.M. Region had some...