Thanks for so many being there, and all most all staying awake.. {:-)
I forgot in the photography portion to bring up something I found
interesting when I read about it in the late 1970's. I pointed out last
night that it took about 5 photons, presumably reflected through the lense
from the photo subject of interest, to render a silver halide grain
developable ...
Now think solid state devices and "gating." Suppose it takes 5 volts to
cause a device to "go on." If a constant bias voltage of 2.5 is always
there then it only takes an additional 2.5 volts to trigger the device.
Now back to film: suppose that the film plane is flodded with 2.5 photons
just before exposure by small LED's in the camera. Then it would only take
2.5 photons of light through the lens to generate a developable grain. This
would mean doubling the effective film speed without increasing the grain
(typically related to film speed.) In the late 1970s the idea was
successfully tested, and it succeeded. Exposure requirements were reduced
by almost a factor of 3 if I recall correctly.. an increase of effective
"system speed" of 3, or 3*400 = 1200 effective speed for TRI-X.
Cheers, and thanks for letting me talk.
John
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