Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@y..., "Martin Wesley" 
<mwesley250@e...> wrote:
> Herb,
> 
> What you say makes sense only if there are a finite number of 
tones. In a
> full range continuous tone silver print there are no steps between 
min and
> max density but an infinite number of tones. If you can achieve a 
continuous
> tone print from a digital source the same would apply there.


Martin -- Well, I'd say that what I say makes sense whether there are 
a finite number of tones or an infinite number that are available in 
a silver printing process.  But that if you think there are an 
infinite number of tones available to an analog process then you 
might just think it's silly to try to compare the 'dynamic range' 
(using Austin's meaning) of the two systems.  So you're left with 
comparing density ranges.  

By the way, I also think it doesn't make much sense to think of there 
being an infinite number of tones available in a silver process (even 
if there are in reality, which seems dubious to me).  Even assuming 
that there were an infinite subtlety of tones in some silver print, 
our eyes are a limiting factor there; there's no way we can 
distinguish adjacent tone steps from another after a certain subtlety 
of step size is reached.  If the dynamic range of digital printers 
increases to reach the ability to print tone steps more subtly than 
we can differentiate between them, then for all practical purposes 
the dynamic range of a digital print will be as great as that of a 
silver print.  

Our sensory perception has also shown up as a limiting factor in 
digitization of music, where even if the analog recordings had 
infinite gradations of tone, the (then more limited) subtlety of CD 
recordings captures gradations of tone beyond our ability to 
distinguish them.  (By the way, I think it turns out that audio CD's 
actually have greater dynamic range (i.e., more subtlety of tone)
than what you can get in an analog process, which kind of goes 
against there being an infinite subtlety of tone possible in silver 
prints.)

Similarly with digital projectors (you know, what businessmen use for 
presentations) and CRT projectors, which are analog.  A digital 
projector that has a resolution of 800 x 600 pixels will display an 
image that looks pixelated and digital if you look at it from a few 
feet away.  But if you move back to several times the width of the 
image you can no longer make out the pixel structure.  For all 
practical purposes, it will then appear seamless; we can no longer 
distinguish between adjacent pixels of the same color.  I know this 
example doesn't have to do with dynamic range of images, but it's 
related, I think.

-- Herb