In the absence of scattering, the attenuance provided by the emulsion is independent of the collimation of the illumination; a dense point absorbs a big portion of light and a less dense point absorbs a smaller portion, irrespective of the directional characteristics of the incident light.
This light is then reflected out through the photophore apterture, where it passes through a brown filter, yielding a far-red light with a maximum absorbance at 708 nm (almost infra-red).