Fig. 6
From: The use of the skylight polarization gradient in young sandhopper’s orientation
(a) Spectral transmittance of the filters and light source used. The black vertical bars show the “window” of wavelengths projected on the sandhoppers during the experiment. (b), radiance measured along the solar meridian of the dome. The West and East parts are equalized when the polarizing filter and the neutral density grey filter are both present. The irradiation along the solar meridian was measured at 10° intervals using a radiometer.
