In the proposed project, we will address photo bathymetry, which is also referred to as ‘through-water photogrammetry’. Our aim is to formulate, implement, and evaluate a comprehensive and rigorous model that goes beyond the common assumption of a static planar water surface. As explained above, the precise elevation and orientation of the water surface is a prerequisite for the strict geometric modelling of refraction. We will, therefore, exploit the photographic image data twofold, in order to simultaneously determine i) the dynamic water surface and to perform ii) the overdetermined photographic ray intersection for 3D water bottom point coordinate determination.