Re: CMYK again


Peter Charles Fredrick (pete@fotem.demon.co.uk)
Thu, 08 Jul 1999 05:53:20 +0000


On Wed, 7 Jul 1999, Judy Seigel wrote:

> Four colur printmaking "CMYK"
> Firstly I print the black printer as a light grey.I use this image as a key
> line image to measure the effect of the colours.Simultaneous contrast makes
> proper evaluation of the yellow difficult, ! a light grey under image
> helps.
>
> Next I print the yellow this colour can be printed at the end or the
> beginning dependent on the yellow used, if a opaque yellow is used then it
> must be put down at this stage such a colour could be cadmium lemon
> yellow.However if you use a Hansa yellow it can be put down last as it is
> transparent There are fores and against's using both systems. You can of
> course us a mixture of the two.
>
> Next I print the magenta quinacridone, this is a tetchy colour which tends
> to coat rather thin so you will probably need two coats to reach a full
> saturation. If you try to build the pigment colour by increasing the
> pigment in the mix you will more than likely run into coating problems

>>It seems relevant to add that Pete and I have compared notes on this and
the conclusion that the different media work differently is inescapable.
For instance the quinacridone red and hansa yellow are both STRONG colors
in watercolor-gum, in fact I had to cut the amount of pigment several
times to get a good "standard" formula. As I recall, Pete is using
entirely acrylic.... I'd also wonder if different brands and modes of
acrylic don't act differently. Did you say which one, Pete?<<

You are quite right Judy, It is not just the pigment media but also the
thickness of the emulsion layer which is determined by the nature and
absorption of the substrate, as always in photo/alt printmaking it is the
final balance of all the constituents that determines, if you change one
you have often to change the lot.

>>For instance, by cosmic coincidence I happen to have out on my table the
Binney & Smith brochure on Liquitex Acrylic Techniques and Mediums. This
points out that the different forms of Liquitex, tube and jar, are
essentially different media. Golden acrylic also makes a LIQUID emulsion
(have you tried that one?)... which was what I used in one or two
experiments with acrylic-gum. (It seemed to work, but there were more
pressing experiments at the time, or seemed to be.)<<

I have in the past used both these Manufactures products and they and they
are excellent colourants. At the moment I am in the process of compounding
my own media from raw pigment, precisely balanced for my Temperaprint
process, I may in the future market these compilations when the research
is finished.

> Next I print the cyan, normally this will be Phalocyanine blue green shade,
> this is a very powerful colour with high tinting strength, so the amount of
> pigment in the mix will be small this makes for very easy printing and it
> is at this stage that the print comes alive and all the colours begin to
> make themselves felt.
>
> The next stage is one of balancing the three colours against each other if
> extra Yellow is required then a transparent Hansa yellow will need to be
> used, as previously explained. This is a very sensitive stage in the
> production of the print and will depend on demands of colour fidelity and
> aesthetic appeal. I am afraid the answer lies only in the eye of the
> beholder nowhere else.
>
> Finally the black is brought up to required strength sometimes I omit this
> stage completely at other times I reinforce the black to add calligraphic
> effect, it entirely depends on the pictorial requirements, of the image.
> This is the methodology I normally use for standard CYMK work but as an
> increasing amount of my personal work is associated to with Polychrome
> presentation, I may change the order for special effect.

>>I get a sense that the black is much less problem in acrylic than
watercolour, though it's much easier in digital than continuous tone....<<

Any black is a dangerous colour, painters avoid it like the plague, but
with care and suitable subject matter, it can be very effective.

>>Don't recall which one you said you use -- was it Mars? That was
impossible in wc. I finally settled on Daniel Smith Paynes gray, either
alone or mixed with ivory black. Best of a bad lot for a *transparent*
black.<<

Yes I use Mars black and the acrylic does help, also the plastic KIMDURA
base that I employ

>>For opaque, gouache is good -- and I suppose with a digital
separation there's no reason not to use opaque ? (you think?).<<

Yes I see no technical reason why an opaque black could not be used
However aestheticaly I prefer a transparent black. My great joy is to look
into the print just sensing the colours underlying the black

> Generally the exposure times are the same, however I do use digitally
> separated negs so this would make sense in these circumstances. However I
> sometimes give long exposure to get the colour right up into the highlights
> and conversely give short exposure's to just get the deep shadows to
> stick, this is normally with black or another colour to give a slight bias
> in the shadow area's.
>
> I hope this helps, my hard drive crashed recently so I have lost a lot of
> my recent email's If anybody is waiting for a reply could you please
> re/e:mail me again thanks

>>That stuff about the hard drive crashing is really ominous -- you're maybe
the 6th just this month. I think it's heading eastward.... uh oh...
(plus of course condolences!)<<

Thank you for your condolences! a hard drive crashing is a nasty kind of hell

Pete

http://www.fotem.demon.co.uk/ To visit petes parlour gallery, there is now a
Guestbook !



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