Re: VueScan: (was: Re: Measuring DMAX

[Katharine Thayer <kthayer@pacifier.com>]

Thanks and aplogies  to those who responded and whose responses I  
didn't see earlier, like Don and Yves.  I don't get all the posts all  
the time, and I have to keep remembering to go to the archives to see  
if there are posts I didn't get.  Anyway, thanks much for solutions  
to the problem.

As to gum print DMax unlikely over 1.1, I've measured gum prints with  
DMax up to 1.8 with a densitometer,  which matched the visual density  
as estimated by comparison to a Stouffer reflection density step  
tablet.  But I had to give the densitometer back so I was intrigued  
by this Viewscan solution to reading densities in an easy and  
straightforward manner.  Just now,  (now that I can finally read one  
value) I looked at a gum print that was near at hand, not one of the  
ones that read as high as 1.8 before, but a one-coat with a somewhat  
lighter pigment mix; according to ViewScan the darkest areas read  
between 1.3 and 1.6.   Marek reported DMax for one-coat gum prints at  
1.4 recently, as I recall.
kt




On Feb 1, 2008, at 11:05 AM, Katharine Thayer wrote:

> On Feb 1, 2008, at 8:46 AM, Katharine Thayer wrote:
>
>
> > Thanks, but not true; my three numbers are all different; I've  
> > never gotten three identical numbers, either in 8 bit or 16 bit,  
> > or even in 1 bit! They generally range over 6 or 8  points, but  
> > sometimes as much as 12 or 15.
>
> I was half asleep when I wrote this; by "6 or 8 points" I meant,  
> like for instance a point I'm looking at now (in 8 bit black and  
> white mode)  that gives me  these three values:  .90 .94  .98.