Re: Profile Editing Thoughts . . .
Re: Profile Editing Thoughts . . .
- Subject: Re: Profile Editing Thoughts . . .
- From: Steve Upton <email@hidden>
- Date: Tue, 26 Jun 2001 00:22:09 -0700
At 5:00 PM +1000 6/26/01, Darrin Southern wrote:
On 26/6/01 8:45 AM, "Steve Upton" <email@hidden> wrote:
I think you have answered your own question here.
UV filtering will probably solve your problem. I am not sure about
this but I am pretty confident.
This fact was in the back of my mind, so I went out and borrowed a DTP41UV,
scanned and built new printer and reference profiles (from the same patches
used with the DTP41 no UV) and I can not see a difference between the two.
It did not fix my issue.
well.. that rules that one out doesn't it!
> Good data from a good print typically builds good profiles. Print
open is good software so you should look at the techniques you used
to print (linearize as much as possible) and measure.
I am using the exact same technique (for BEST and PrintOpen) that I use to
build the HP5000 profiles - these could be used without editing, although I
am to get them 'closer' by editing.
OK so you should be at least in the ball park....
The only question I have is regarding the Proof Setting for Media White
adaption in PrintOpen page 4-70 of the manual. This option sound like my
issue, but only made a slight improvement
Is this 'metamerism' or optical brighteners, or both ?
Doesn't sound like either, brighteners are probably out as the UV
spectro didn't make a difference.
Also a possibility is the white point of your proofing profile.
Spectros do not always do a good job of measuring the paper white and
that simple number has a huge effect on the final color if absolute
colorimetric proofing rendering is enabled.
I am not simulating paper white (a BEST rip setting).
OK - so that's ruled out too.
Have you isolated the profiles? This is why you should test them in
Photoshop. you need to print a known-good RGB image through the paper
profile to test it. If it prints well then you are looking at a bad
proofing transform in the "reference" profile. If not, then the paper
profile is at fault.
Not that it uncovers the cause for the yellow cast but at least you
know where to edit.
That reminds me - I agree with Andrew about editing the proofing
profile - mostly - you really need to isolate where the problem (in
this case the yellow cast) lies. If it is in the paper profile, you
could edit the reference profile to remove the cast but then when it
is used to proof elsewhere (like on screen) the yellow edit will mess
up the softproof.
One last idea. You should still check the white point of the profiles
and make sure they are in the ballpark. Even though you are not
simulating one on another, they are still used in the color
calculations and if they are messed up, could be contributing to the
problem.
Regards,
Steve Upton
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