I have a question regarding measuring natural illuminant spectra underwater. I see that in the sample data file there is a csv for “5m green water 400-700 nm”. Could you share the technique of how this was measured? I’m interested in doing something similar but would like to know if the illuminant spectra should be measured in the same viewing plane as the animal or if measuring downwelling irradiance is ok.
Jolyon is spot on. One issue that we have been discovering is that, if your grey standard is not lambertian you might run into calibration issues when you have it illuminated sideways (i.e. in shallow water with lots of light coming from the top but the image taken sideways e.g. of an anemone or a wall). The measurement of the light environment is pretty straight forward, just as Jolyon said.