🚀 go-pugleaf

aluxelocochon@yahoo.com wrote:
> Hello,
>
> I hope you guys can help me. I recently made an ad in adobe
> illustrator which has a greyscale image with an orange to transparent
> gradient on top made by creating an opacity mask. Well on the screen
> it looks fine and so I sent it to the comercial printer. However when
> the comercial printer gave us the proof it shows a sort of lighter
> hue band in the area where the orange gradient ends and meets with
> the grey image below. In other words, instead of the gradient
> blending smoothly with the grey image below (as it shows on screen!)
> there is like a lighter strip that just almost ends abrouptly and
> looks bad where the gradient ends.
>
> This same thing had happened to me with almost the same ad in the same
> place when I took it to Kinkos to print. However this time the
> gradient and the greyscale image were one rasterized bitmap image
> exported from photoshop. The guy in kinkos was telling me that it is
> a problem that appears because the image has an area of just k and
> sudddenly it goes to color and it not always goes smoothly. Well I
> told him that in my printer at my office that didn't come up, but he
> told me again about the k to color problem which was odd to me
> because this time it was just one image like a photo so I don't see
> how that could be my problem. Anyways I suggested he try printing it
> from another printer there at kinkos and he did and this time it came
> out without any problems. So that solved it that time.
>
> But my current case is that the proof from the comercial printing is
> showing this band again, so my question to you all is this: Is this a
> problem that the Comercial printer should solve or is there something
> I can do to correct this in the illustrator file?
>
> Any help/suggestions will be really appreciated.

It would be helpful to know what type of printer it is.  Is it a laser
printer?  And it would also help to know what type of file you are
providing - CMYK?  Third, are you using a custom profile to generate the
CMYK file, or leaving this to Kinkos.

Few people would provide even a guess without knowing both of these, but der
Curvemeister loves to step across the plate and swing at pitches like this
one, so here goes.

If the answer to both of these is yes, then look at the K plate and look for
a loss of density or other banding at the point in question.  Since the
problem involves orange, look carefully at the Y plate - monitors are poor
at representing light, saturated yellows.  Whichever channel the problem is
in, a good way to hide the transition is by adding a strategic amount of
noise.

Anopther possibility: custom profiles are a famous source of gratuitous
banding - get hold of the profile in question and run it on some gradients,
and see if it introduces its own banding.
-- 
Mike Russell
www.curvemeister.com