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RE: filmscanners: Nikon MF LED light source...
> > Many
> > scanner documents have used the term DMax interchangeably with dynamic
> > range.
>
> They are wrong to do so :)
I disagree that it is "wrong". There may be another way that you believe is
clearer (and I don't disagree), but that doesn't make this way wrong.
> DMax is a measure of the minimum transmissive opacity of a film.
> DMin is a
> measure of the maximum transmissive opacity. Dynamic range is DMax-DMin.
DMax is of no value what so ever unless there is a DMin associated with it
(and vice versa). Typically, DMin is assumed to be 0 when DMax is used by
it self. DMax is equal to the dynamic range if DMax is referenced to a DMin
of 0. Plain and simple. Having a DMax of 4 and a DMin of 1 is exactly the
same dynamic range as a DMax of 3 and a DMin of 0. The dynamic range is
still 3. All density values are ratio values, and are therefore relative,
and all you need to know is what the number is relative to. Without a
relation, density values are useless. Dynamic range does not need a
relation, as it is a "range".
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