In previous paper (part 1), the authers reported the principles and the new techniques of photogrammetric measurement in tidal current surey. This specific techniques for applying photogrammetry to the measurement of currents is discussed, and the practical test was done at Akashi Seto (Akashi strait), Japan, on 11th November 1965. In this test, air photographs were taken using two aircrafts each mounting a camera equiped with synchronized shutter apparatus, 450mμ cut filter and pancromatic films. Just defore taking photographs, pieces of chemical foam sheet (polyethylene paper) were scattered from 23 fishing boats for floating targets. Charts of iso-current velocity contours and of vector were made by means of plotting these syncronous stereo photographs on a Wild A-7 plotting instrument. The result of the procedure were analyzed with another informations, details aspects of sea-surface obtained by interpreting the photographs. It is concluded that the application of photogrammetry to current measurement is practicable and may prove extremely valuable in oceanological field.

View full abstract