Re: PSO Coated v3 separations
Re: PSO Coated v3 separations
- Subject: Re: PSO Coated v3 separations
- From: Refik Telhan <email@hidden>
- Date: Tue, 28 Aug 2018 19:37:11 +0300
- Thread-topic: PSO Coated v3 separations
Hi All,
Is this discussion taking us to a point where we have to discard Adobe
Photoshop as a conversion tool? Where and how are the files converted by the
color server be checked, ie proofed (soft and hard)?
Back in the old days, ProfileMaker 5 had one nice feature. You were able to
choose between "Paper Colored Gray" and "Neutral Gray" when setting the
"Perceptual Rendering Intent Option".
Below is the excerpt from the help file of ProfileMaker:
----------------
Perceptual Rendering Intent Option
Daily work shows that different aspects are frequently required for ideal
implementation of a gray axis. ProfileMaker therefore provides two methods for
defining the gray axis. These definitions affect only the Perceptual Rendering
Intent.
With Paper-Colored Gray, the substrate color of the scanner/camera testchart or
the paper color of the print run affects the entire color space. This may shift
the gray axis of the image. Colors in the image may end up with a cast although
they are in fact neutral. This means that even a medium gray still has a yellow
cast on a yellow paper. In printing, this corresponds to the use of the same
printing plates for papers with different colors (paper white).
Note: From the technical point of view, this corresponds to relative
colorimetry with shadow compensation.
With the Neutral Gray option, the substrate color or paper color only affects
lighter areas. In the other color areas, the colors and gray axis of the image
are preserved to the best possible extent, and are not influenced by the paper
white.
Note: This corresponds to relative colorimetry in highlight areas and absolute
colorimetry with shadow compensation in the remaining colors.
Note: The default and recommended setting is Neutral Gray.
For example, if B/W and color images are positioned next to each other in
reproduction, the Paper Gray Axis option should be selected to achieve the same
impression in the neutral tones both in the B/W images and in the color images.
Conversely, if an ad is produced that must be reproduced with identical results
in offset printing and in gravure (with the exception of highlights that are
allowed to differ on account of the different papers used), the Neutral Gray
option should be used when generating the offset and gravure profiles.
Note: The Perceptual Rendering Intent calculation options Paper Gray or Neutral
Gray don't affect the proofing process. In the proofing process the Relative
Colorimetric or Absolute Colorimetric Rendering Intent is used.
----------------
These profiles that used this Neutray Gray option works fine with Photoshop
when Perceptual rendering intent is used.
Can FOGRA51 and FOGRA52 based profiles be recalculated to function is much the
same way? Or at least could we have a variant of the profiles that can do this
kind of neutralization?
Regards,
Refik Telhan
On 22.08.2018 23:00, "colorsync-users on behalf of Andreas Kraushaar"
<colorsync-users-bounces+rtelhan=email@hidden on behalf of
email@hidden> wrote:
Hi Martin, all,
this is a „problem“ or a „feature" with ICC based white point scaling
(required for colorimetrical encoding of data). Rendering neutrals from ab=0,0
to ab=2,5 -10 is quite a change and XYZ-scaling from black to white does not
reflect the required XYZ to be printed to actually get a decent print. The
solution would be to use a perceptual rendering intent that does a grey mapping
close to ab=0,0 and not to what XYZ scaling predicts.
I know many color server device link profiles (F39 - F52 and also ECI-RGB
to F52) that does this job.
regards
Andy Kraushaar
PS: So please believe me that the people that doing this huge (unpaid)
efforts also do check the separation, yes!
Wir stellen den Hintergrund in den Vordergrund.
We put the background in the foreground.
—————————————————————————
Dr.-Ing. Andreas Kraushaar
Abt. Vorstufentechnik
Fogra
Forschungsinstitut für Medientechnologien e.V.
Einsteinring 1a
85609 Aschheim b. München
Telefon: +49 89. 431 82 - 335
Telefax: +49 89. 431 82 - 100
E-mail: email@hidden
Internet: www.fogra.org
-----------------------------------------------------------------
Geschäftsführer: Dr. Eduard Neufeld | Sitz des Vereins: Aschheim b. München
| Vereinsregister 4909
> Am 21.08.2018 um 23:49 schrieb Martin Orpen <email@hidden>:
>
> Is it just me that thinks that FOGRA51 produces inferior separations and
unacceptable skin colour?
>
> Just like FOGRA52 we get separations that lack yellow when we need MORE
yellow to create an acceptable skin colour.
>
> Who makes the decisions about colour reproduction for these standards?
>
> Have they proofed and printed the BVDM Roman 16 images with the Green and
Blue backgrounds?
>
> Did they honestly believe that skin the colour of boiled ham was
acceptable?
>
> This causes a lot of problems in pre-press workflows because clients
supplying Photoshop CMYK end up with terrible looking images and any that we
edit using commercial separation software (that corrects the yellow deficiency)
look nothing like the images in the rest of the job.
>
> This wasn’t the case with FOGRA39.
>
> The new standards are producing substandard results :(
>
> --
> Martin Orpen
> Idea Digital Imaging Ltd _______________________________________________
> Do not post admin requests to the list. They will be ignored.
> colorsync-users mailing list (email@hidden)
> Help/Unsubscribe/Update your Subscription:
>
>
> This email sent to email@hidden
_______________________________________________
Do not post admin requests to the list. They will be ignored.
colorsync-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden
_______________________________________________
Do not post admin requests to the list. They will be ignored.
colorsync-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden