Digital BW, The Print

I see a lot of paper manufacturers talk about whiteness and opacity 
when describing their papers.  I always think in Lab terms when 
thinking of the brightness and color of the paper (and wish they'd 
provide that data).

For example, the data sheet for Innova Cold Press specifies a whiteness 
of 88.32%.  Is there any correlation between "whiteness" and Lab 
numbers?  Can I determine or estimate the Lab values from their 
whiteness value?

Also, what does the opacity number mean?  The above paper specifies an 
opacity of 98.95%.

Thanks,

Lou

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Louis Dina" 
<lou@...> wrote:
>
> I see a lot of paper manufacturers talk about whiteness and opacity 
> when describing their papers.  I always think in Lab terms when 
> thinking of the brightness and color of the paper (and wish they'd 
> provide that data).
> 
> For example, the data sheet for Innova Cold Press specifies a 
whiteness 
> of 88.32%.  Is there any correlation between "whiteness" and Lab 
> numbers?  Can I determine or estimate the Lab values from their 
> whiteness value?
> 
> Also, what does the opacity number mean?  The above paper specifies 
an 
> opacity of 98.95%.
> 
> Thanks,
> 
> Lou
>

Hmmm..........I may have partially answered my own question.  Looks 
like everyone has their own system, and brightness and whiteness 
don't necessarily correlate to Lab measurements.  Here's a Xerox 
article on the subject which clarified things a little, but didn't 
provide the answer I was hoping for.

http://a1851.g.akamaitech.net/f/1851/2996/24h/cacheB.xerox.com/downloa
ds/usa/en/t/ThreeKeyPaperPropertiesWhitePaper.pdf

Lou