Digital BW, The Print

David Kachel <david@...> wrote:
 
> I put a lot of effort into getting the exact shade of brown I desire and don't want it to change to some other brown in ten or twenty years.

Do you have the Lab A and B values for a 50% midtone of your ideal warm tone?

What I suspect is that the brown you are looking for is both warmer than the carbons we have and has a Lab A that is closer to the Lab B value than what carbon has.  Carbon tends to be more of a yellowish warm as opposed to a "chocolate" warm.

Jon Cone's carbon sepia is probably the best warm 100% carbon inkset.  There are members of this forum who can probably give you some Lab coordinates for some papers with that inkset.

MIS glossy compatible carbon sold as LK and LLK (among others) on a paper like Crane Silver Rag will have a Lab (a, b) of about (4.2, 12.8).  With a paper like EEM the values would be about (2.9, 7.3).  For this EEM, the paper white Lab values were (0.9, -1.1).  So, the change was (2, 8.4).

The Aardenburg-Imaging fade test of Cone Carbon Sepia on H. Photo Rag shows a Lab (a, b) at 50% of (3.3, 8.1).  There the paper white was (0.7, 0.7).  The change here was (2.6, 7.4); not all that different from the MIS carbon.

There are some matte papers that are warmer than these.  But, my experience with measuring the classic sepia tones and mixing the MIS sepia toners for the UT2 and UT7 is that a true sepia has a Lab B of closer to 20 -- considerably warmer than these carbon inks.  

For a more "chocolate" look, the Lab A needs to be closer to the Lab B value.  I have not seen any carbon ink that can do that.  The Cone sepia and MIS PK, LK, & LLK carbons are about as warm as I've seen.

Ideally, I think a toner ought to be a single pigment type so that the fade path is straight back to carbon.  Some of the newer red or orange pigments would be interesting to experiment with in this regard.  The Aardenburg-Imaging fade tests might show which ones would be most lightfast.

Finding a good, solid, true sepia or way to get to one easily is an interesting issue.  My guess is that a single LK density red or orange toner might be enough, but I have not done those experiments.

Paul
www.PaulRoark.com