VTR-Pictures taken under water are usually used for aquatic ecological study in situ. The VTR-Pictures contain valuable and various information. For evaluateing qualisy of VTR-Pictures, and studying about a model of lingt-transmission under water, we use data from experiments and deta from real-sea observations. We present a new method how we can estimate quality of VTR-Pictuers by a pattern-boad. Without any trouble some considerasions about light-transmission parameters, We can handle a VTR camera in the sea easily by this method.
　Motion-analysis of suspended tracers are attempted for its application. Our motion-analysis method is based on travel distance between a pair of serial scenes. We also show limits and errors of this mehtod. We apply this method for the estimation of local flow field VTR-Pictures taken in Tokyo Bay. It shows good ability of advanced application of underwater VTR-Pictuers.