Here’s a finished board, with the LEDs that are used as senses attached to wires made more rigid with heat shrink (this hides the resistors as well). The peculiar colour cast of the image is due to a coloured light being on in the background.
And here’s a plot of the light levels detected by each sense as I shone a light at them and shaded them with my hands.
I’d love to make a group of these and hang them up to experience their environment. I think I’ll port the code to Processing.js so they can run online as well.