Digital BW, The Print

This paper is OBA free; yet it has an unusually low Lab B -- slightly negative according to my spectro. Apparently Canson claims to add some "natural minerals" to achieve this whiteness. Does anyone know what they are adding?

I profiled the paper for the 7800 and Eboni-6. It has a good dmax and prints on the warm side, with a maximum Lab B of about 5.

Paul

www.PaulRoark.com

On 11/20/2013 07:24 AM, roark.paul@... wrote:
> This paper is OBA free; yet it has an unusually low Lab B -- slightly
> negative according to my spectro.  Apparently Canson claims to add some
> "natural minerals" to achieve this whiteness.  Does anyone know what
> they are adding?
>
>
> I profiled the paper for the 7800 and Eboni-6.  It has a good dmax and
> prints on the warm side, with a maximum Lab B of about 5.
>
>
> Paul
>
> www.PaulRoark.com

Yes, for a OBA free paper it is very close to neutral. I think in your 
case the UV-cut spectrometer has been compensated too much by the 
software expecting an OBA paper due to the Canson's high reflection just 
above 420 NM. My UV enabled i1Pro + Share says b 1.9, Mark McCormick's 
Spectroscan etc meters keep it on b 1.0. So in both cases slightly 
warmer. All the other OBA free papers are warmer, one or two come close.

An alpha cellulose paper with almost alike paper white in reflection and 
color is the Innova IFA 24 Decor Art 210 gsm and its dual sided version 
IFA25. A little more texture though and by its weight less opaque.  Much 
cheaper for proofs and posters. You will like it. IFA25 can also be 
found disguised as Harman by HM Matt Fibre Duo and Hahnem\ufffdhle Photo Matt 
Fibre Duo. My best guess is that the alpha cellulose fibre is of a very 
white quality where the Canson Rags (BFK that I use has it too) depends 
on a very white quality of the rag + high quality whitening agents. So 
the IFA24 probably will yellow earlier.

Kaolin, barite are all natural minerals. TiO2 less due to the 
manufacturing process. With a scientific spectrometer it would be much 
easier to check which whitening agents are use. Can't afford that.



-- 
Met vriendelijke groet, Ernst Dinkla

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
December 2012: 500+ inkjet media paper white spectral plots.

What minimum LAB L value do you reach?

Pascal