Human Eyes as an Image Sensor

This is a pretty old 2001 Yoshio Fukui notes, but it's still a best summary of human eye properties expressed in image sensor terms I've seen. Few quotes:

Spectral sensitivity:
Light-adapted eyes: 400 – 700 nm (peak at 555 nm: yellow light)
Dark-adapted eyes: 380 – 650 nm (peak at 507 nm: green light)

QE:
At low luminance = 5%
At high luminance = 0.5%

A slightly expanded version of Yoshio Fukui lecture is here.