Digital BW, The Print

>>> For my
>>> work I couldn't live with just 256 shades of gray and would still be
>>> sloshing around in the dark.
>> 
>> Hmm. Next time you're working a grayscale image on your computer change
> your
>> monitor from millions of colors to 256 shades of gray and tell me if your
>> image looks any worse for wear.
> 
> Todd,
> 
> I tried it and the on screen image looks terribly degraded and posterized in
> comparison to 32-bit color monitor setting.

Really? You selected grayscale, not 256 shades of color? The difference must
be in our graphics card. No matter.
 
> I really wish I had some comfort level as to how many shades of gray can be
> perceived by the human eye or at least a range since there is bound to be
> person to person variation. I have heard 100, 256 up to 1030. The most
> thorough study which I neglected to save was done in Sweden and they
> reported that most people could differentiate between 800 and 900 shades of
> gray but that artists and people in the graphics industry could see 900 to
> the 1030 number. Unfortunately they did give any details of how the testing
> was done. I hate newspaper articles about scientific tests.

I'm sure it depends on how they test for this stuff. The test methodology,
as well as the environmental conditions, will obviously have a huge impact.
I wonder if every institute even performs the same test, and if so, is it
even a well designed test?
 
> I think that if it is some fixed number of say 256 you can have multiple
> sets of 256 tones in an image that contribute to its impact. Say you could
> only differentiate 256 but you had 1024 tones. Your eye could see the
> difference between 1 and 4, 4 and 8, 8 and 12, etc. You could also
> distinguish between 2 and 5, 5 and 9, 9 and 13, etc.

I have no idea how it all works. I guess the point is how many tones are
needed to trick perception into believing all the tones are present. How
many tones can be deleted before the eye notices them as missing. That sort
of thing.

I mean it doesn't even seem to be cut and dry as to whether staying in a
16-bit workflow and printing 16-bits through the Piezo driver makes a
visible difference in print, and that can be the difference between 256
shades and tens of thousands. (And to those who've heard that printing
16-bits through piezo does make a visible difference, I need to ask, did the
8-bit version it was compared to contain all 256 tones? You have to give the
8-bit version a fighting chance...)

Todd