[Leica] MTF explanation

[Carsten Bockermann <Carsten_Bockermann@compuserve.com>]

Erwin,

>>MTF: why is the contrast transfer above 100% from 1 to 20 cycles/mm?
>>Some developerscan be designed to maximize what is called "adjacency
>>effect" or "neighbourhood effect". 

I donīt think one needs to rely on the edge (or neighborhood) effect to
achieve contrast above that of the original scene. There is film material
(like lith film) out there that has an extremely high inherent contrast.
Itīs just a matter of non-linear reaction of the film material to light.
One example usually associated with low light photography is the
Schwarzschild effect.

Carsten

http://ourworld.compuserve.com/homepages/Carsten_Bockermann/