Re: [Leica] HiRes Photography (2)

["Jacques Bilinski" <jbilin@axionet.com>]

> So the choice of the true, physical image plane relative to the true
> geometrical focal length determines the reproduction of the image point.
Now
> my research indicates that you can select a location of the filmplane,
such
> that the intersection of the bundle of rays favors a broader sectin of the
> cone of light, which means high contrast but low resolution. Also it is
> possible to select a location that favors the most thin diameter of the
> paraboloid, which invariably means high resoltion but soft contrast.
> This is just what the Japanese did: their lenses had he same properties as
> the German ones, but they choose a different location of the effective
film
> plane.

Erwin, I'm having some difficulty understanding this. Is 'choosing the
location of the film plane' the same as what is commonly refered to as
'focusing' or is it something the lens designer does when designing a lens.
Because if it's the former it is the photographer or lens tester doing the
choosing (except off course at the min focus distance or (usually) at
infinity).