Build of DeviceN Spot Colours in a PDF

[Stephen Marsh]

If one has a PDF file that uses DeviceN spot colours, how can one tell what the actual build values for that colour are in Acrobat Pro?

The Ink Manager does not display a build for the colour.

The Convert Colours / Document Colours / Colour Spaces does list that the alternate colour space for a DeviceN space may be "alt=deviceCMYK"- which sounds like an non-ICC referenced CMYK build... but what are the build values/recipe?

One could of course take the PDF into Illustrator or Photoshop to see what the build values are for a certain DeviceN spot colour, however one would think that there is a way in Acrobat Pro.

A client could build the spot colour values as RGB, CMYK or Lab mode, could they not?


Sincerely,

Stephen Marsh

 

[Lukas Engqvist]

You will not find the build values in Illustrator or Photoshop, only the alternate values, so it will give same result as in Acrobat pro. You will need a pantone book to get the recipes. CMYK values are device/substrate dependant if you have a specific colour in mind.

 

[Stephen Marsh]

Thanks Lukas, yes, the alternate values were what I was talking about, sorry for not being more clear. So how does one see the alternate CMYK spot colour build alternate values in Acrobat? Convert the spot colour to CMYK? What other colour modes can the spot colours be in, RGB or Lab? I have only come across device CMYK and ICC CMYK in the two jobs that I have been looking at.

What I am trying to find out is what are the recipe/build for the spot colour alternate colour - within Acrobat Pro.

EDIT: I have confirmed that standard Illustrator spot colours can have RGB or Lab alternate colour builds, however I am not sure if deviceN (from an Esko PDF) differs in the alternate builds allowed.


Cheers,

Stephen Marsh

 

[Glenn McDowall]

Pitstop sometimes reports the Alternate color space percentages.
Typically from Quark you see conflicting definitions for the same DeviceN on an object by object basis. Often quark objects have Alternate space Lab and placed EPS have Alternate space cmyk.

 

[Lukas Engqvist]

OK, yes in a RIP you sometimes have a Lab table, and CMYK tables for coated and uncoated etc.
I think both Illustrator and InDesign includes Pantone libraries with both, Photoshop uses the Lab values for Pantone and Acrobat inherits the choice of the host application. I think it is possible to get the values from a preflight script, maybe somone else knows more. (Pitstop showed info about alternate colour space but haven't used it since 4.6)

 

[Stephen Marsh]

Thanks for the replies!

I am using inkjet proofing RIP software that for now shall remain nameless.

It has both OEM/Licensed and end user defined spot colour look up tables. If the spot colour build/definition/recipe is not found in these two libraries - then the RIP can use the colour information defined in the file to produce the colour in question.

We have a client that does not wish to use the colour found in the file, however this colour produces the best output in a certain specific complex interaction of inks.

If the end user look up table can be built using the same values as those found in the file, then the issue should be "solved" (unless this is a deeper issue of how the RIP works behind the scenes).

So, if the alternate colour is a CMYK build, then I will just have to open the PDF into Illustrator or Photoshop to inspect the build of the spot colour - unless I can find the right preflight script (ideally using PitStop or other PDF plugs).

Wishlist: Adobe to add a feature to the Acrobat Pro ink manager that indicates the build of the alternate colour found in the file for all spot colours.


Cheers,

Stephen Marsh

 

[mattbeals]

Have you used the inventory report in Acrobat Pro to see what color spaces are used? I don't have such a job handy but it might report the values. Along those lines you can use callas pdfToolbox or PitStop to remap the alternate color values for the spot colors.

 

[Stephen Marsh]

Thanks Matt, yes, as Lukas mentioned - one of the preflight analysis scripts will report the alternative colour builds. It is not as easy as looking in the ink manager, however the feature is there.

The preflight tools that Adobe licensed from Callas do have a lot of power and information in them - it was just that my first thought was to look in a more obvious place such as ink manager and convert colours. In future I will have to remember to give preflight a deeper look.

Best,

Stephen Marsh

 

[rich apollo]

PitStop will only show the alternate color values if those alternate color values are in CMYK, and there are no ICC profiles present.

 

[rich apollo]

PitStop will only show the alternate color values if those alternate color values are in CMYK, and there are no ICC profiles present - otherwise you get information like "Alternative Color Space: RGB".

Playing with one of the Preflight mechanisms is reporting values different than those used to build/define the spot color. Hmmm, and I was so happy just a little while ago.

 

[Glenn McDowall]

Playing with one of the Preflight mechanisms is reporting values different than those used to build/define the spot color. Hmmm, and I was so happy just a little while ago.

I never quite got to the bottom of it but I was getting really weird cmyk splits as an alternative colour space to a Photoshop Duotone EPS (with two PANTONES) placed into quark8.1 and either Exported via JAWS or Print Postscript then Distill. There seemed to be some heavy duty unwanted color management going on. The only way I got photoshop's build numbers was Export (ps for later Distilling) PDF and use Distiller. The same duotone EPS in InDesign exported out as Nchannel, so different again.