Digital BW, The Print

> Ratio of minimum and maximum contrast.

B-b-b-b-b-but Martin, isn't maximum contrast (dMax - dMin), and minimum
contrast the "smallest discernable [tonality]"?

> This fulfils the basic definition and is not as obtuse as it would appear
> from the DyR equation.

For photographic use, I'd agree with that!

> The equation is just a subtle change on
> the basic max
> to min ratio

What's the change?  The definition of "min" and "max"?

<snip>

> Austin is
> not wrong in
> applying his contrast ratio to a photographic print but he has failed to
> demonstrate how this would be done or what value it would have when
> comparing two printing mediums.

For me, that's a separate issue...I wanted to get to the point where the
basic concept was understood first.  I take it you now understand/agree with
the statement "dynamic range of a photographic image is (maximum contrast /
minimum contrast)", and not the same as the density range?

Regards,

Austin