Publication

Fundamentals of in situ digital camera methodology for water quality monitoring of coast and ocean

Goddijn-Murphy, Lonneke
Dailloux, Damien
White, Martin
Bowers, Dave
Citation
Goddijn-Murphy, Lonneke; Dailloux, Damien; White, Martin; Bowers, Dave (2009). Fundamentals of in situ digital camera methodology for water quality monitoring of coast and ocean. Sensors 9 (7), 5825-5843
Abstract
Conventional digital cameras, the Nikon Coolpix885 (R) and the SeaLife ECOshot (R), were used as in situ optical instruments for water quality monitoring. Measured response spectra showed that these digital cameras are basically three-band radiometers. The response values in the red, green and blue bands, quantified by RGB values of digital images of the water surface, were comparable to measurements of irradiance levels at red, green and cyan/blue wavelengths of water leaving light. Different systems were deployed to capture upwelling light from below the surface, while eliminating direct surface reflection. Relationships between RGB ratios of water surface images, and water quality parameters were found to be consistent with previous measurements using more traditional narrow-band radiometers. This current paper focuses on the method that was used to acquire digital images, derive RGB values and relate measurements to water quality parameters. Field measurements were obtained in Galway Bay, Ireland, and in the Southern Rockall Trough in the North Atlantic, where both yellow substance and chlorophyll concentrations were successfully assessed using the digital camera method.
Funder
Publisher
MDPI AG
Publisher DOI
10.3390/s90705825
Rights
Attribution-NonCommercial-NoDerivs 3.0 Ireland