Recovery of underwater object reflectance
The reflectance of underwater objects at a certain depth can be obtained with knowledge of the radiance illuminating it at that depth. Here we recover the reflectances of underwater objects using the color signal from a standard target of known reflectance. An estimate of the at-depth radiance as measured from the surface is obtained using the diffuse attenuation coefficient k(z,λ) and Beer's Law. Since k(z,λ) estimates require the same integration times for measurement at different depths, we develop a technique to recover the spectrum at one integration time given the spectra captured at other integration times. All measured and estimated spectra are found to agree.