Re: Barry Stein: problems with WZI target and profiling

[Horses <support@horsesLLC.com>]

Barry Stein wrote:
>
>
>I have noticed that the printed targets seem to be dark with too much
>magenta.  Is it possible that the program can not calculate a good profile
>because the printed target is too far out of range?

This shouldn't happen with a good profiling package. The target is SUPPOSED
to print dark, since the idea is to print it without any color correction.

However.... ... ..

a) The target should NOT be printed in such as way that the ink soaks through
the paper. This obviously means that too much ink was used in the target
print. When RGB targets are being printed through the Epson driver, it's
typically not possible for this to happen, because the Epson software
itself apparently has some built-in ink limitation. When CMYK targets are
being printed through PressReady, however, all bets are off. MatchLock
automatically limits the ink in that case (so that we get a good, clean
CMYK target print). None of the other packages do.

>What I meant is that I thought it was impossible to differentiate some of
>the color gradients in the target because they were too dark.

b) The target should NOT be printed so that color gradients in the target
block up. You're perfectly correct. If the target isn't well designed,
or if it prints too darkly (regardless of any ink limitations), or both,
then you can correctly surmise that the profiles calculated from measuring
this target will suffer. All of the color patches in the target should
print so that they are distinguishable in the scan that results. The MatchLock
printer calibration target is designed that way.

>I did get
>what I thought was a slightly better profile when I used the "photo film"
>setting on the printer instead of "photo paper" or "photo inkjet paper" to
>print the target and the final print. The photo film setting did lighten the
>target print slightly (I think I read somebody's post that it reduces the
>amount of ink put on the paper).   I think I might try to print the target
>in photo shop with a set amount of brightness increase and then add that as
>an adjustment layer to my final print with the new profile to see if it
>helps with the problem.  My thinking here may be flawed but what the heck
>it's only two more sheets of paper.

I don't think this will work, but it sounds like anything's worth a try.
It's not acceptable that you should have to play games with the target,
before you print it, to build a decent profile. (IMHO).

Regards,

David Miller
Horses 

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