A few years ago, Lee and Carder demonstrated that for the quantitative derivation of major properties in an
aqua-environment (information of phytoplankton biomass, colored dissolved organic matter, and bottom
status, for instance) from remote sensing of its color, a sensor with roughly ~17 spectral bands in the 400 −
800 nm range can provide acceptable results compared to a sensor with 81 consecutive bands (in a 5-nm
step). In that study, however, it did not show where the 17 bands should be placed. Here, from nearly 300
hyperspectral measurements of water reflectance taken in both coastal and oceanic waters that covering both
optically deep and optically shallow waters, first and second derivatives were calculated after interpolating
the measurements into 1-nm resolution. From these hyperspectral derivatives, the occurrence of zero value at
each wavelength was accounted for, and a spectrum of the total oc-urrences was obtained, and further the
wavelengths that captured most number of zeros were identified. Because these spectral locations indicate
extremum (a local maximum or minimum) of the reflectance spectrum or inflections of the spectral
curvature, placing the bands of a sensor at these wavelengths maximize the possibility of capturing (and then
accurately restoring) the detailed curve of a reflectance spectrum, and thus maximize the potential of
detecting the changes of water and/or bottom properties of various aqua environments with a multi-band
sensor.
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