ICC profile

[dwilson]

Hello, I am looking to place photos that are 300% ink density in InDesign and be able to save them as 260% ink density. Is there a profile for this?
I want to place rgbs that are 300% into InDesign and save the pdf and the files come out cmyk at 260%.
I know the profile U.S. Web Uncoated v2 which if used will save the file as 260% in Photoshop and I am wondering if there is one that will do this in InDesign.

Thanks for any help ahead of time.

[Lukas Engqvist]

There is more to a profile than the total ink.
Yes it is possible to convert files in the same way as you do in Photoshop. It is possible to convert all RGB data to the CMYK profile of your choice (you set that as working and document CMYK) and when you export to PDF you choose convert all colours to working/document CMYK (or simply convert to a PDFx1a)

Now what ICC profile to use? Are you going to coated, uncoated or newsprint? Take a look at
colormanagement
I hope you can find what you are looking for there.

[dwilson]

I am using the U.S. Web Uncoated v2 profile.
I just did a test in InDesign with your suggestion and it did not convert the photo to the profile above, and that was using the PDFx1a. Will this only change rgb to cmyk or will it actually change the ink densities? I do understand there is more to the profile than just ink density. But I am trying to get from A to B in InDesign.
I appreciate the link! Lots of great information!

[mattbeals]

If you are placing RGB into InDesign and having InDesign convert to SWOP v2 upon export then the ink limits and other profile settings will be used to convert from RGB to CMYK. If you have CMYK in the document that have an ink coverage in excess of your desired value InDesign cannot help you. You need to reseparate the CMYK images by: 1) Using a device link profile in PhotoShop or after the PDF is made; 2) in PhotoShop convert to RGB then back to CMYK; 3) in PhotoShop convert to LAB and then back to CMYK.

There are a variety of color servers out there than can do this. Preflight/correction tools like callas pdfToolbox and Enfocus PitStop can convert RGB to CMYK AND apply device link profiles. The device links that Enfocus and callas can apply to the PDF can be RGB to CMYK or CMYK to CMYK links.

Similarly you can use device link profiles (CMYK to CMYK only) in PhotoShop CS5.

You may be better served sending PDF/X-4 files with a defined output intent of US Web Coated SWOP v2 and NOT having the color spaces converted. You leave them as they are and include all source profiles. Then the recipient can manage the color conversions for you. Including any CMYK to CMYK transformations.

[Louis Dery]

You need to reseparate the CMYK images by: 1) Using a device link profile in PhotoShop or after the PDF is made; 2) in PhotoShop convert to RGB then back to CMYK; 3) in PhotoShop convert to LAB and then back to CMYK.

Hello Matt,
In Photoshop, the only good and accurate way to lower the ink coverage with ICC profile is the 3rd option you’ve suggested (CMYK to Lab to CMYK). Converting to RGB and back to CMYK is not a good advice.

Best regards

Louis

[mattbeals]

Louis, you're right but that is unfortunately still a common practice...

[Stephen Marsh]

Hello Matt,
In Photoshop, the only good and accurate way to lower the ink coverage with ICC profile is the 3rd option you’ve suggested (CMYK to Lab to CMYK). Converting to RGB and back to CMYK is not a good advice.

Best regards

Louis

Louis, I have to disagree with this view.

Both in theory and in practice, I have not seen any major visual difference in converting in the following methods in Photoshop:

1) Convert from the source CMYK direct to the new CMYK profile

2) Convert from the source CMYK, to an intermediate RGB*, then to the new CMYK profile

3) Convert from the source CMYK, to an intermediate Lab mode, then to the new CMYK profile

In all of the above cases since Photoshop 6, the colour transform takes place through the ICC profiles PCS, or profile connection space - which is usually L*a*b*. One should note that although the PCS may be L*a*b* based, this is not the same thing as actually converting the pixels from CMYK to Photoshop Lab mode.

I think that the "best" modern approach in Photoshop using ICC profiles is #1 listed above. Even better would be to use a Device Link Profile in current versions of Photoshop. Some would argue that option #3 is worse than option #2. There is no need to convert to an intermediate space when one can go direct from CMYK to CMYK (unless one wishes to make subjective edits between conversions, such as increasing shadow density).

One can do better though with an action or scripting. If reducing total ink limit is the major concern, there is no real need to totally reseparate the entire image - when it is only the shadows that over over the limit. One can kludge together a "mock" DVL conversion.

*RGB can be many "flavours" - a smaller gamut such as sRGB, to a larger gamut of say Adobe RGB or ECI RGB, to a very large gamut like ProPhoto RGB or Wide Gamut RGB. Spaces such as ProPhoto will do a better job of clipping 100% pure yellow from CMYK than smaller spaces. sRGB will clip saturated cyan. This may not mean much to "natural" images that do not contain 100% pure primary colours, as opposed to synthetic images such as test targets that do.


Sincerely,

Stephen Marsh

[Louis Dery]

Hi Stephen,

My comment was about CMYK to CMYK conversion for ink limit normalization. Since it is not possible to convert to the same CMYK profile (which make a null transform), the CMYK to LAb to CMYK must be made.

If the need is to convert to a DIFFERERENT CMYK profile which has a lower ink coverage, THEN you can simply do a conver to profile.


Louis

[Stephen Marsh]

Hi Stephen,

My comment was about CMYK to CMYK conversion for ink limit normalization. Since it is not possible to convert to the same CMYK profile (which make a null transform), the CMYK to LAb to CMYK must be made.

If the need is to convert to a DIFFERERENT CMYK profile which has a lower ink coverage, THEN you can simply do a conver to profile.


Louis

Thanks Louis, that was not clear earlier in the topic, and now that you have clarified your post - I am none the wiser!

So, if the destination profile is the same as the source - why would it normalize or change the ink limit? Should they not be different? And if they are actually different with the same internal profile name...why?


Stephen Marsh

[rich apollo]

Hello, I am looking to place photos that are 300% ink density in InDesign and be able to save them as 260% ink density. Is there a profile for this?
I want to place rgbs that are 300% into InDesign and save the pdf and the files come out cmyk at 260%.
I know the profile U.S. Web Uncoated v2 which if used will save the file as 260% in Photoshop and I am wondering if there is one that will do this in InDesign.

If the photos are RGB then this is simple. Upon the export of the PDF, simply "Convert to Destination (preserve numbers)" in the Output tab of the Export dialogue.

If the photos are CMYK, then you must "Convert to Destination". The downside is that this will also convert everything else in the document, including your black text, et cetera.

Now, if you export without converting, you can use the "Convert Color" tool in Acrobat. This will allow you to convert only images. You can set up parameters to convert CMYK and RGB images differently, for example you might choose different rendering intents.