ON THE CALIBRATION OF UNDERWATER CAMERAS

Abstract

Abstract Analytical plumbline and serf calibration techniques are applied to the calibration of two underwater cameras: a Rolleifex SLX réseau camera with an Aquamarin WKD‐SLX/6006 submarine housing and a Nikonos V underwater camera. The Rolleiflex was fitted with a 50 mm Distagon f/4 lens and the Nikonos with a 28 mm Nikkor‐UW f/3.5 lens. Comparisons of the results from the two methods of camera calibration are described. Theoretical differences are predicted for in‐air versus in‐water values for radial distortion. When these are compared to the actually observed values of distortion, an insight is provided of the precisions claimed for each method of camera calibration.