Sorry, now that I've started thinking about this stuff for the first
time in 15 years more and more is coming back to me.
A special separation trick for very dense images. ie: lots of ink on the
paper.
Most printers will lie and cheat in this particular situation, be warned.
Your separation is called CMYK for a very special reason. Technically
that is the order in which the printer has to put the colours down on
the paper in order for the image to appear as the designer intended. So
Cyan and Magenta go down first, then the Yellow.
But the yellow ink is the slowest drying of all of them, and you're
putting it down on paper that's already wet with 2 layers of ink. And
then you have to try and get the black down without smearing over the
top of that. If your boss insists on buying cheap rubbish inks it
actually never dries at all. So the printer cheats, he does the print
CMKY with the Yellow last. With very dense images it's actually
impossible to do it any other way, the paper is still only paper.
So if you have a particularly dense image you want mass produced talk to
the printer before you do your separation. Don't talk to the sales rep,
he usually has no clue. Talk to the actual offset printer tradesman that
will be printing that job, let him decide if your separation needs to be
CMYK or CMKY.
It's also a good idea to talk to the actual printer about what papers to
use, after all, he's the one that has to try and get the ink to dry and
he knows what papers will give what jobs the best results. The sales rep
is just trying to quietly drain your wallet and will repeat anything
that the sales rep from the paper company said even if he knows it's not
true. Some papers are so alkaline that we had to stack customers jobs
carefully in the backs of every one's cars and reverse them all out in
to the full sun for a few hours to try and get them to dry. And I'm
talking Australia here, not them cold places like Europe and the US.
Cheers,
Andrew.