For all those who are interested, I referenced one of my father's engineering books from the 1940's
" The Scientific Basis for illuminating engineering" by Moon. When I was in university, this book was still well known to the professor I had teaching the same subject.
In the book, there is a nice little graph that shows the average area of the pupil, adjusted to level of light.
at 10e-6 lumens/sq foot, the area of the pupil is 50 square millimeters, and at 2000 lumens per square foot it is about 3 square mm.
This gives 2 interesting points, the range of apatures and the overall working range of the eye. The working range is a ratio of 2 billion to 1, or about 31 stops total range.
if we consider the change in area the eye can stop down 6 stops this means the cornea is good for a dynamic range of something like 25 stops.
There is also discussion about resolving power of the eye, with different tests. the eye can resolve 2 stars at 1 minute of arc, 2 black bars on white background at 1/2 minute of arc, or a vernier scale (multiple bars) at .15 minutes of arc. Here they state the typical spacing of the cone receivers in the eye is about 3 microns.
Focal length is also noted at 15mm
OK guys, now that you have some real data go at it.
Last edited by Lowell Goudge; 02-23-2008 at 06:44 PM.