Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@y..., "Austin Franklin" <darkroom@i...> wrote:
> Roy,
> 

> > I only claim that your argument
> > of 8-bit can't
> > make 1000 levels is flawed.
> 
> I never said it CAN'T make 1000 theoretically...just that I doubt it
> actually DOES in reality.  What's flawed?  Where is the flaw?  Precisely...
> Don't simply say something is flawed, and not say what about it is flawed.
> I've been VERY precise with my disbelief in the 1000 tone claim, citing
> reasons why I believe the physical hardware and inks don't do it.

The only reason I've seen is: 2^8 = 256 < 1000.

> 
> > The problem is you can't
> > PROVE it false mathematically.
> 
> I CAN PROVE it mathematically.

Did you leave out the word "false" intentionally?

  I've ALWAYS said that, and completely
> understand how it THEORETICALLY can be done.  And, as I've said, you don't
> need four inks to do so.  That merely reduces the area you need to do it.
> 
> > All either one of us can do is speculate
> 
> Not so.  I can ask to see an example that shows 1000 tones.  That's not
> speculation at all.  I simply don't want to speculate, I want to know if the
> claim is true or not.

Why don't you ask Jon Cone if the claim is true or not.   
Realistically, I've never seen marketing material backed up with lots of 
absolute proof, examples, and test procedures.

  Not mumbo jumbo theoretical fluff.  This is reality.
> Does there exist a print that was printed with Piezo that has 1000 distinct
> tones.  Can I print a 1000 tone step wedge and discern all 1000 tones.
> Simple question.  Tyler was kind enough to give me a 256 step wedge.  I will
> print it, and chart the results.  If I can't measure 256 distinct tones with
> my X-Rite 810, then I am even more skeptical that it can print 1000.

I wish you luck in this try, but I wonder if you've thought this out.  As far as
I can tell from the online spec sheet of the X-Rite 810, it reads in 0.01D units.
Since the dmax you're likely to get is less than 2.00D the number of distinct
readouts from your X-Rite has to be less than 200.  So I'm quite sure you'll
get less than 256 distinct measurements regardless of whatever the piezo
system prints.  Also, did you consider the area of measurement for the
X-Rite?  The spec says 4mm so I'll assume that really means 4mm^2.
At a mere 300ppi = 12ppmm input file, we've got 4*12*12 = 576 pixels
of the original file under that densitometer.  That's quite a large sampling
average.  BTW, a 256 step wedge comes right on the piezo software
CD -- that's what I used for the exact same test a couple of days ago.


> 
> > BTW, a little aside:  I noticed on the piezo website that the claim of
> > 2160 dpi is now qualified by the word "effectively" -- a nice addition.
> 
> And that is an issue that I've had too, as the physical hardware can simply
> not do that, as far as I can tell from the service manual and the Epson
> programming documentation I have access to.  The printer is only hardware
> capable of 1440...and Jon made a claim that there are more commands that the
> printer has than the ones published...and I believe that...but whether any
> of them actually allow you to get around the physical hardware limitation is
> still left unexplained...

Geez, Austin, the word "effectively" nullifies Jon's original claim.  It no
longer says it prints "at 2160 dpi" which several of us rightly thought
was physically impossible.  The current quote is "effective resolution of
2160 dpi" which is sufficiently vague as to not really claim anything.

The point is you WON that argument, we all won that argument.

> 
> Regards,
> 
> Austin

Roy