Digital BW, The Print

Clayton,

You wrote:

>You entered 0 for the warming amount for the MIS FS black - how can
>that be?  I use that ink in my BO printing and it definitely warms,
>though not nearly as bad as the full ink set.  Is this a mistake?

No mistake.  The FS-K appears to do better in the 100% patch than in
midtones.  Although I must confess I was a bit surprised myself that no
warming at all occurred.

I've come to the conclusion that the FS-K does have a bit of dye in it.  The
co-solvent, apparently, causes the dye to "aggregate" -- clump together.
This forms masses, perhaps especially with pigment particles, that act more
like pigments in some respects due to the clumps' larger mass per surface
area.  This action appears to be most effective when the ink mass is most
dense.  Perhaps in the midtones it is less effective.  With the full inkset,
where it is diluted with non-co-solvent base, the aggregation is also very
diluted or lost altogether, so the apparent dyes act like what they are.

However, the dyes must be a small percentage of the total.  They "burn off"
relatively rapidly and then the fade rate slows down substantially.  The
warming with the FS inkset is probably mostly the dyes burning off.

>So it looks like the Epson Matte Black is top dog - wasn't the
>Archival supposed to be better?

Some could read the tests as indicating that the Matte Black is tougher than
the Archival Black.  Although neither faded at all in the 100% patch, the
Archival Black did warm very slightly.  Frankly, I suspect the very slightly
better performance of the Matte Black is an artifact of the testing.  In
better-controlled tests and the real world, I'd bet on the Archival Black.

The fading and warming in these tests is not linear.  So, what does best at
first may not do better over the long haul.

Also, any test that does not hold the humidity constant exaggerates
longevity.  The heat of the lamp dries out the test samples, eliminating the
moisture that is a very big factor in fading.  I'd guess this effect is much
greater with the non-coated UC Matte Black than with the coated Archival
Pigments.  I'd bet that coating will help protect them in real world
situations, but it probably does little or nothing in a test like mine.  To
a certain extent, the comparison may be "apples and oranges."  The
relatively short testing that I and others do without the 60% humidity may
be mostly a determination of the extent of dyes in the mix.  As such, as we
move to ever better, more pure pigments, the informal testing may reach its
limits.

I'd go with Wilhelm and Epson on the relative lives of these pigments, and
Epson claims the Archival are much longer lived.

That said, I have the Epson Matte Black in my 1160 now.  I find it a very
interesting ink.  I'm getting a dmax of over 1.60 on Eclipse with the Epson
driver, and with the Archival K midtones it's a very neutral combination.
So, in terms of degree of blackness combined with fade resistance, I do
think it is top dog in some respects.  (I have not tested the new PiezoTone
Museum black.)

My main concern is whether the UC Matte K causes more trouble with the
printer.  The UC Matte black FS/Piezo-compatible inkset I mixed ultimately
caused vertical "banding" or waviness in the prints.  I also think that I
have more bad nozzle checks with it in the printer.  So, while I think the
UC Matte Black has great potential and I hope these problems are unrelated
to the inkset, I do have some concerns.

Paul
http://www.PaulRoark.com

___________________________________________________



> I've double-checked my numbers and added the missing ones to the
table.

>                      300 HOURS TEST RESULTS
>
> 2200 Ink            Fade   Warm    EAM Dmax
> --------------------------------------------------------------
> Epson Matte Black     0      0     1.73 1160/BO
>
> Epson Archival Black  0     .02    1.48 1160/BO
>
> MIS Matte Black      .07    .02    1.58/1.51 BO
>
>
> -----------  Non 2200 Ink for comparison
> MIS FS Black         .02     0     1.61/1.59 1160/not BO


You entered 0 for the warming amount for the MIS FS black - how can
that be?  I use that ink in my BO printing and it definitely warms,
though not nearly as bad as the full ink set.  Is this a mistake?


>One problem with the dmax readings is that EAM and EEM
>from the various batches I have are so different.
>Note that all the fade testing of the group was on a
>relatively late batch of EAM, not the new EEM.

Understood, but that's ok because I've been using the old EAM and that
gives me a good value to compare with.  For me it's all relative.  The
numbers don't mean much except if it's higher or lower than EAM then I
have a realistic comparison.  I'm using an 870 which I like very much.
I'm not in a hurry, but someday I'll probably upgrade to a 1280 or
2200.  It just depends on the inks.

So it looks like the Epson Matte Black is top dog - wasn't the
Archival supposed to be better?

Regards, - cj

Paul,

>>>>
No mistake.  The FS-K appears to do better in the 100% patch than in
midtones.  Although I must confess I was a bit surprised myself that
no warming at all occurred.  I've come to the conclusion that the FS-K
does have a bit of dye in it. ...
>>>>

Ah, this explains a lot of things. 

>>>>
Some could read the tests as indicating that the Matte Black is
tougher than the Archival Black.  Frankly, I suspect the very slightly
better performance of the Matte Black is an artifact of the testing. 
In better-controlled tests and the real world, I'd bet on the Archival
Black.  The fading and warming in these tests is not linear.  So, what
does best at first may not do better over the long haul.  Also, any
test that does not hold the humidity constant exaggerates
longevity.  
>>>>

Understood.

Thanks very much for the report.  This is really filling in a lot of
blanks and I'm sure other readers are following along.

Best Regards,
Clayton