Converting CMYK to RGB

[purushoth_j]

Hi,

I am having some folder full of both Pixel and Vector based artworks. All in CMYK mode. Now I want to convert all these assets from CMYK to RGB color space/mode and use it for an RGB typesetting workflow in InDesign. Before doing that I really want to know what are the issue I will face while converting and using these artworks in RGB InDesign document. Please share your inputs.

Best regards,

Purushoth 

[Test Screen Name]

Why not just led InDesign concert as needed? What specific reason do you see for converting the assets first?

[BobLevine]

RGB typesetting? For what purpose?

And, I hate to tell you this but once it's CMYK, you've effectively thrown away too much data to convert it back to RGB without it being quite lossy. The color gamuts are just too different.

If you can back up and tell us exactly why you're trying to do this, maybe we can help but also tell us your InDesign version and operating system.

[JonathanArias]

from indesign you can export an interactive .pdf (RBG) or print .pdf  (CYMK).

you don't gain colors when going from CYMK to RBG. When you covert from RBG to CYMK colors are lost. you however can't put colors back/add by converting.

please explain further on what you are looking to do

[BobLevine]

I think that’s a bit too general, Jonathan. Exporting print gives you multiple presets as well as the ability to save your own.

Some, such as PDF/X-4 keep colors unchanged so if you use RGB (which in any modern workflow should be used) they remain RGB.

[rob day]

Some, such as PDF/X-4 keep colors unchanged so if you use RGB (which in any modern workflow should be used) they remain RGB.

Hi Bob, If the end use is web viewing X4 could be a problem because color can be inconsistent depending on the browser and the object color modes. The OP might be wanting to get all of the color into sRGB so the color appearance is preserved in any browser—that conversion can happen on export, but not with the X4 preset.

[BobLevine]

Right. I was thinking more for print production.

[JonathanArias]

this subject can be complex.

i work with CYMK and RBG graphics in my layout. and just export to interactive .pdf.  i have experience issues with that pharma branding green they like to use.. it becomes neon on ipad.

For print i just choose the highest setting available in the presets and let indesign do the rest.

[rob day]

i have experience issues with that pharma branding green they like to use. it becomes neon on ipad.

Did that happen with an interactive export? Older versions of iOS and many desktop browsers can't color manage CMYK color with no profile, and the displayed color can really vary—that's why you want to force a conversion to sRGB. Both PDF/X-1a and PDF/X4 export document CMYK colors as DeviceCMYK (no profile).

[JonathanArias]

yes, it was on the interactive .pdf.

[rob day]

InDesign lets you mix objects with different color spaces and profiles on the same page. So if you are wanting to sample colors from placed CMYK objects and use it for type fills, you can use the Eyedropper tool.

For images the sampled color's mode will match the mode of the image, for vector art it will be a color managed RGB color matching the appearance of the vector's CMYK color. Any sampled color or swatch can be converted into a different color space, and the conversion will be color managed. So in the case of CMYK images you can sample and convert the CMYK color into your document's assigned RGB space, and use it for type color fills, via either the Color Picker or the Color panel.

If you want to export the entire document to a PDF in a single RGB color space (i.e., sRGB), you can do that by setting the the Destination in the Output tab to the desired RGB profile. Interactive PDF exports convert all color into profiled sRGB.