Acrobat Output Preview

[Kristian]

We've had a couple of issues recently with the Black separation in Acrobat. On some jobs, areas that are 100% Black show as a mix of all 4 process colours when using the output preview in Acrobat. I have changed the Simulation profile to various ones but it still keeps showing the 4col Black.

The PDF has been generated by a customer using InDesign CS4. I've exported PDF's myself but they always display correctly in Acrobat.

Any ideas what settings they are applying when generating the PDF? It's annoying as the first PDF was sent back telling them their separations are incorrect when actually they weren't. When imported into ArtPro it comes in as 100% Black only.

Screen shots attached.

Thanks for any help.

Kristian

 

[Duncan Hyde]

We've had a couple of issues recently with the Black separation in Acrobat. On some jobs, areas that are 100% Black show as a mix of all 4 process colours when using the output preview in Acrobat. I have changed the Simulation profile to various ones but it still keeps showing the 4col Black.

The PDF has been generated by a customer using InDesign CS4. I've exported PDF's myself but they always display correctly in Acrobat.

Any ideas what settings they are applying when generating the PDF? It's annoying as the first PDF was sent back telling them their separations are incorrect when actually they weren't. When imported into ArtPro it comes in as 100% Black only.

Screen shots attached.

Thanks for any help.

Kristian

Hi Kristian ask the client if they can export the PDF as a PDF/X-1a: 2001 format that usually takes care of a lot of issues for prepress. The black text should remain as 100% black only.

Take Care - Duncan

 

[Kristian]

Thanks Duncan.

The artwork does separate correctly, it's only the preview in Acrobat that is incorrect. I can contact the customer but it's happened on a few various files and I just wondered what was causing it.

 

[Duncan Hyde]

Oh - Sorry sounds like colour profile issues, yes they can give you different output values I'll let you know if i hear more about it

Duncan

 

[Kristian]

Oh - Sorry sounds like colour profile issues, yes they can give you different output values I'll let you know if i hear more about it

Duncan

Thats it! You were right it was colour profiles in InDiesgn. If 'Convert to destination' is turned on this causes the preview in Acrobat to display incorrectly unless you choose the actual profile that was assigned.

See screenshot attached. In Acrobat if I choose Euroscale Coated as the simulation profile I will get a 4 colour Black but if I choose FOGRA39 (as chosen in InDesign) it will display correctly.

Thanks for your help.

Everyday's a school day!

 

[CHM]

To avoid mishaps in the future, maybe you would direct your clients to here: Ghent PDF Workgroup | Download Application Settings | Application Settings

There you can find everything you have to do, including the application setting, to deliver a good pdf file.

 

[mattbeals]

If you embed an output intent when exporting from InDesign Acrobat will use the output intent to display the document in output preview.

 

[Duncan Hyde]

Well great happy to help, you see these blogs are great and i agree i learn something everyday like going back to school

Take care

Duncan

 

[leonardr]

Thats it! You were right it was colour profiles in InDiesgn. If 'Convert to destination' is turned on this causes the preview in Acrobat to display incorrectly unless you choose the actual profile that was assigned.

Acrobat is displaying 100% correctly!!! It is doing EXACTLY what you told it to do...

If you use device DEPENDANT colors (eg DeviceCMYK) then your color values are UNDEFINED - UNTIL you associate them with a given profile. And if the profiles don't match, then the values MUST be converted according to the rules of the PDF Reference/ISO 32000-1 which refers to the rules of the ICC.

As someone else said - use PDF/X (I prefer PDF/X-4, but X-1a is fine). That is an international standard that will ensure you that did the right things for improved color fidelity. and the recommendation to use the guidance of the GWG is also excellent.

leonard

 

[Kristian]

Acrobat is displaying 100% correctly!!! It is doing EXACTLY what you told it to do...

If you use device DEPENDANT colors (eg DeviceCMYK) then your color values are UNDEFINED - UNTIL you associate them with a given profile. And if the profiles don't match, then the values MUST be converted according to the rules of the PDF Reference/ISO 32000-1 which refers to the rules of the ICC.

As someone else said - use PDF/X (I prefer PDF/X-4, but X-1a is fine). That is an international standard that will ensure you that did the right things for improved color fidelity. and the recommendation to use the guidance of the GWG is also excellent.

leonard

Ah I see. Makes sense I suppose. Thanks for your help.

 

[rich apollo]

It would be helpful/useful for the Output Preview dialogue to indicate if it is displaying actual file values or values that are going through a color transform. Maybe the box could be split as in Photoshop to show file values and 'proofing values'.

 

[mattbeals]

Maybe in output preview we can a warning indicator that there is no output intent defined or you are displaying device cmyk. I guess at that point though you could use the built in preflight to see if an output intent is defined or not and then decide how to handle the file. Or at the preflight stage assign an output intent.

 

[leonardr]

It would be helpful/useful for the Output Preview dialogue to indicate if it is displaying actual file values or values that are going through a color transform. Maybe the box could be split as in Photoshop to show file values and 'proofing values'.

Acrobat NEVER displays the raw "file values" - it ALWAYS treats them as values against the ICC profile that is defined as being the source profile...whether it is embedded as ICC colors, OutputIntents or Working Space preferences. So it's easy to know .

 

[rich apollo]

Prepress routinely needs access to the "raw 'file values'". It'd be a great addition.

 

[leonardr]

Prepress routinely needs access to the "raw 'file values'". It'd be a great addition.

But raw values (for device colorspaces) have no meaning! This is especially true in the context of the various standards such as PDF/X where the values are directly associated with the OutputIntent.

 

[toronar]

It could be another reason that Acrobat displays 100% black as 4-color black.

(I am using Pitstop's naming of objects here)
If you have an object that is colored Multiple Spot Colors (NChannel) and 1 spot color "Black" with an alternate color space that is an ICC-Profile, Acrobat will render it as 4-color black on screen, whereas a RIP and Acrobat will ignore the alternate color space and produce 100% black upon output.

Acrobat has to use the alternate color space for the screen preview and will convert the 100% black to the ICC-Profile and ends up with 4-color black.

(see screenshot)

 

[Thierry]

I completely agree with leonard but Acrobat's output preview can be really misleading for people who don't understand how it works. I see a lot of professionals (especially printers) sending back files to their customers and telling them that those files contain 4-color blacks. At least, with Acrobat 9, you can use the object inspector and check if an object (image, text or anything else) is tagged with an ICC profile or is seen as deviceCMYK. In the first case, you can choose this same profile as the simulation one and check the "real" values.

 

[mattbeals]

If we can get more people to adopt PDF/X then we can avoid much of this miscommunication by using the embedded output intent. This "simple" (I know it's not always that simple for customers) bit of communication is a godsend. In most situations that I have run across assuming (not always a good idea) that untagged CMYK is SWOP v2 has worked well. Like i said, if we can just get them to embed an output intent much of this goes away...

 

[Lukas Engqvist]

There are alot of things you can do with the colour converter (yellow to blue gradient in the prepress tool bar). If you unembed ICC profies the values will be device-CMYK and therefore independant. Your art will then also chane its visual appearance as you choose to view with different output profiles. You can also force off (not recommended) colour managemenr in Acrobat pro in the print dialogue.

I find that using the Convert to output intent and preserving black (and pure colours in some cases) is the best way to nail down the appearance of a PDF to resolve the unambiquety for coworkers down the line. (usually I will bounce this to the customer so that they can take their share of the responsibility)

 

[prepressguru]

To avoid mishaps in the future, maybe you would direct your clients to here: Ghent PDF Workgroup | Download Application Settings | Application Settings

There you can find everything you have to do, including the application setting, to deliver a good pdf file.

Great website thank you!