Cropping RGB to CMYK values

[christianherbstreuth]

Hello,

i work in Photoshop, use eciRGB V2 and later convert to PSO Coated v3

As usual the colors get paler after conversion etc - so far everything is clear.

I'm looking for a function to simulate the later CMYK result while working in RGB color space - not only latently via > View > Color Proof, but e.g. as a settings layer on top of my layers and dynamically cropping the result to the colors printable in CMYK.

Is there such a function ?

[D Fosse]

Why is proof not satisfactory? That is the most accurate preview you can get - you see exactly, in real time, how the printed result will look (as long as you have a wide gamut monitor that covers the target color space).

If you also want to check numbers and histogram as you go, you can use smart objects. Convert the eciRGB document to a smart object, and then convert that to PSO Coated.

Double-click the smart object in the Layers panel, and the embedded eciRGB file opens in a separate window.

[christianherbstreuth]

Proof is only a visual check. 

I need an automatic, dynamic cropping of my Picture while retaining all the advantages of the RGB colour space (filters etc). 

The Smart Object is a nice workaround - I will check if this makes sense in practice ... Thanks

[Mylenium]

Assuming actually picking safe colors is the issue regardless of what profile is active, you might wanna try magicPicker or similar. Those tools have built-in options for alternate gamuts or force-limiting color selections.

Mylenium

[christianherbstreuth]

I will have a look on magicPicker – Thanks

[NB, colourmanagement]

Hi

you ask 

I'm looking for a function to simulate the later CMYK result while working in RGB color space - not only latently via > View > Color Proof, but e.g. as a settings layer on top of my layers and dynamically cropping the result to the colors printable in CMYK.

Is there such a function ?

I don't believe there is

proof colours satisfies most users. 

I hope this helps

neil barstow, colourmanagement.net

[please do not use the reply button on a message in the thread, only use the one at the top of the page, to maintain chronological order]

[christianherbstreuth]

Thanks...

I'm trying to establish a workflow at an agency.

The goal should be that the graphic designers can no longer send RGB layouts to clients that cannot be converted to CMYK in the same colour later - so the impression is different. Therefore an automated solution would be the best ...

[rob day]

The goal should be that the graphic designers can no longer send RGB layouts to clients that cannot be converted to CMYK.

Are the agency designers creating the page layouts with InDesign? You seem to be describing a problem that a PDF/X workflow addresses.

It would just be a matter of setting the InDesign layout’s assigned CMYK profile to the print destination, making sure Overprint Preview is turned on, and exporting to a PDF/X standard. With ID’s Overprint Preview on out-of-gamut process RGB colors are dispayed in the assigned document CMYK space, and Separation Preview displays document CMYK output numbers even for RGB or Lab objects. A simple startup script or a listener script could enforce the Overprint Preview.

If the export is to one of the PDF/X presets, the X standard requires an Output Intent profile (the document’s assigned CMYK profile). If the client views the PDF in Acrobat, the output intent will be used by default as the simulation profile, and out-of-gamut RGB process color will preview in the output intent’s CMYK space. Or the agency could explicitly make the conversion on a PDF/X-4 export by choosing Document CMYK as the Destination forcing all color into the print destination space.

[christianherbstreuth]

They do their image editing, composings etc. in Photoshop - therefore everything has to match in color

[rob day]

The PDF/X workflow is designed to solve the problem you are describing, but you have to use the PDF/X standard, otherwise there will not be an Output Intent, which displays RGB colors in the output gamut. The client needs to view in Acrobat and not a browser or lower end PDF reader.

[rob day]

An eciRGB image with out-of-gamut color in PS and placed in ID with Overprint Preview off

PS Proof Setup set to PSO Coated and InDesign with Overprint on—results in matching CMYK simulations:

Exported for the client to PDF/X-4 with no color conversion, the RGB color is unchanged but displays for the client as it will convert into the CMYK Output Intent profile:

[christianherbstreuth]

Thanks – i will check that later : )