Byron Angel wrote:..... Very interesting material, Dunmunro. Thanks for posting.
Question: Did the document discuss "utility" factors separating stereoscopic and cincidence type range-finders? - for example, the ability of stereoscopic systems to range upon indistinct images which lacked a clear vertical element to be "cut" by coincidence type units.
Byron
The UK RFs were of the Inverted Strip Field type and didn't require a vertical line for a cut:
Still another comparative study by the Princeton Laboratory at Fort Monroe reports the performance of the M1 stereoscopic Height Finder in ranging on aerial targets with "Mickey," an early form of radar developed for anti-aircraft ranging. (361) Mickey was later adopted by the Army as SCR-547*. This the was made in August 1941, early in the development by the Bell Telephone Laboratories of portable radar sets to be used for this purpose. In all, 125 aerial courses were flown and about 50 of these were analysed The range varied from 1,000 to 18,000 yard In some courses the range was constant, in others it increased or decreased at varying rates, or reverse its direction several times. Both level and dive courses, were included. Highly experienced stereoscopic operators were used on the experiment. The statistical analysis of the results indicates, for Mickey, the precision error ranged from 5 to 78 yards, with a mean precision error for all courses analysed of 27 yards. Seventy five per cent of all precision errors lay between 16 and 36 yards. The consistency error for Mickey is Animated at 25 yards. Average course errors ranged from -16 yards to 87 yards with a mean of 25 yards and standard deviation of 25 yards. 68 per cent of the average course errors lay between -1 and 45 yards. The standard deviation of total range error is about 25 yards up to 7,000 yard range. It then increases, averaging 33 yards for all ranges up to 10,000 yards. The range error is relatively independent of range for Mickey as compared with the M1 Height Finder, which is subject to errors proportional to the square of the range. The optical Height Finder M1 appears superior to the radio range-finder Mickey for ranges less than 3,000 yards; they are equal for ranges between 3000 to 5,000 yards; and Mickey appears superior for ranges greater than 5,000 yards. Experiments designed to discover the of the major sources of error in Mickey were unsuccessful."
