U of S | Mailing List Archive | alt-photo-process-l | Re: my pigment dilutions

Re: my pigment dilutions



Katharine, see below:

25 Ekim 2008, Cumartesi, 10:15 pm tarihinde, Katharine Thayer yazmış:
>>> Dear All,
>>> At this URL I posted a visual of my pigment dilutions:
>>>
>>> http://christinaanderson.visualserver.com/Text_page.cfm?pID=2076
>>>
>>
>> Thanks for that, that's helpful. Will analyze more deeply (by
>> comparing
>> our yellows) but at first sight it seems that both of the my planned
>> magenta and pthalo concentrations are considerably stronger (in
>> proportion
>> to yellow) than yours.
>
>
> I think this may have more to do with pigment choice than
> concentrations, Loris.   The PY 151 is a very light pigment; to my
> mind it simply can't hold its own with most magentas and cyans and
> for that reason I don't recommend it for tricolor but prefer yellows
> with a little more oomph to them.

I've just made a test (albeit a clumsy one):

I mixed 2.5 to 3 part PY151 + 1 part PV19 Rose + 1 part PB15:3 over a
sheet of Yupo. I didn't measure exactly, just eyeballing the squeezed out
paint amnts. Hence the designation "clumsy", and the uncertain proportion
of Yellow.

See the result below:

http://www.loris.medici.name/gum/2.5-3Y_1M_1C.jpg

The black section above is a fully exposed and developed glossy RC print
that I use as reference black in scanning (log 2.0 or slightly more print
density). Below this, you can see a patch made by mixing paints. I
averaged inside the white square and the color sampler says it's R17 G15
B13 (L2 a1 b1 in Lab mode) relative to Dmax of a glossy RC S/G print. From
this I understand Y > M > C; Yellow is pulling both Green and Red Up, and
since Blue is less than Green that means Cyan is weaker than Magenta (if
not, then Blue would be stronger than Green). Correct me if I'm wrong
please - because all this color stuff is still new to me. Anyway, this is
quite convincing black (both in terms of density and neutrality), would
you agree? In the light of this, can we say PY151 can hold its own with
PV19 Rose and PB15:3, or should I test it using a different method?

Thanks,
Loris.