Angelo,
I don't think you ever got an answer to your original question below, so here are
some pointers.
[....
However I am an novice at creating profiles using their software and a
densitometer. Is there anything like a primer on getting started making curves?
...]
Unfortunately not - for now, the best advice is to load an existing profile (you may
have seen some in our files section) and tweak from there.
An important shortcut for toning on the 2200 is that you can vary the ink limits as a
way to increase or decrease the effect of the toning inks. If you load a profile that
tries to produce a neutral print by adding magenta and cyan, you can simply go up or
down on the ink limits without messing with curve points.
Also, since you have an X-Rite 810, you can pretty much take any existing profile for
the 2200, linearize it and you are good to go.
If you like sepia, take a look at my extreme sepia profile in our group files here. It
deliberately uses yellow to go even warmer than the gray ink. You can linearize that
as well as a neutral profile and then freely move beetween the two by using the
blender function in OPM. Again, you are spared the complexity of the curves if you
are not comfortable using them.
[.......
Thought I'd start with trying to
make a near black only curve by adding light black for the 2200 in the spirit
of Clayton Jones. I expect the result would be very warm, but it might be a
way to learn the ropes.
....]
I remember making a black only profile last spring - it may still be in the files, if not,
let me know and I may be able to dig it up. It's not a bad way to learn the ropes as
you say.
[........
Looking at the seven-ink curves, they seem to have wonderful swooping
transitions from one ink to another. Am looking for a guiding rational behind
all of this.
.....]
The principle - which applies to all software that tries to partition the gray scale
across several gray inks - is that you try to use the lightest possible ink for a given
density in the gray scale. And the reason for that is that you want to minimize the
device dots as much as possible.
So, for example, starting from the lightest step in the scale, you use the lightest of
gray inks (yellow-position in dedicated bw systems, or the light gray in the 2200). It
makes the dots at those densities hard to see - as you have found out by using black
only and seeing how prominent the dots are then.
But as you get further down the scale, the light gray ink will obviously not be able to
keep up with the needed density. So, another ink is brought in. In the case of the
2200 with OEM inks, that's the black. In dedicated systems, that can be the magenta-
position ink.
At this transition, you have a few dots of the darker ink kicking in at the same time
that you have near 100% of the lighter ink "on top" of them. So, even though those
dots would be visible by themselves, they are masked by the previous ink. Further
down the scale, the lighter ink is phased out as the middle-gray ink takes over.
Remember what you saw in the black-only scale: Dots are most distracting at the
lower percentages (0-10%). As you get towards the middle (50%), they look more like
fine grain (the dither has the effect of a mezzotint). So as the middle ink takes over
the middle of the scale, its dots are less visible. This is not an option with the 2200,
so you have to rely on hiding the beginning of the black ink under a sufficient density
of the gray ink. Thankfully the device dots for the 2200 are small enough that you
can get away with that. But to some, a middle gray would still be desirable.
As you then appproach the black end of the scale, you have to bring in the black and
make sure it gets to 100% intensity at the 100% mark of the scale. That much is self-
evident.
What is not as intuitive, however, is that you have to cut back on the other inks at that
point, or else your paper will be taking too much liquid and the black will not go
down in full intensity. That is why you see the curves for the other inks "swooping"
down before they get to the 100% mark. That makes everything but the black ink
have a bell shaped curve (though they're not as symmetrical as a real bell shape).
Systems with 3-4 grays deal with this end a little different than the 2200 - allowing
some cyan-position ink to run under the black - but that's another story.
This in short is the principle of partitioning inks to make up a continuous grayscale.
I have described it refering to IJC because that's what you are using. But it holds true
for all gray printing software whether they all give you, the end-user, such control
over each jet or not. The big benefit of approaches like IJC or QTR is that they are
open to be used with any paper and ink for the supported printers.
But by giving you all this control, you, the end-user have to become knowledgeable in
making profiles (and many find it a steep learning curve). Other approaches - such as
ImagePrint - takes the controls away, but makes it easier to make good prints out of
the box.
Antonis