jeff miller wrote:

...

The human eye figure of 100:1 is the most surprising. The low contrast
of film is also surprising. I guess it (re film) shouldn't be, I know
that MgO is the most reflective substance as far as diffuse reflectors
go. I forget the figure.

Photographic paper is often coated with barium sulfate -- baryta --
under the emulsion.

Jerry
--
Engineering is the art of making what you want from things you can get.
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