Colour conversion from RBG to CMYK - any help please?

[jediavenger]

Hi all.

Here's the issue ...
I have set up an RGB document in Photoshop in which the colour works well.

I did so as the image my client sent my was RGB and I followed the colour way (I know - silly me!)

The documents I create are for commercial print, and therefore I need to convert to CMYK.

The blues in the imagery are totally washed out (see image - RGB on the left, CMYK on the right)

I know why this is ... less colours in the RGB gamut than CMYK, etc.

My query is, are there any ways or means to convert the colours in the CMYK space to look as close as possible to the blue of the RGB.

Probably a long shot, but hoping someone will come through for me with a solid answer.

Thanks everyone,

James

[Test Screen Name]

You can't make blues like the RGB design, using CMYK. I suggest you get hold of a CMYK swatch from your commercial printer (or follow their recommendations to obtain one: these are not cheap and they won't give you one...) Then you can choose the best blue in the swatch and recolour part of the image. This would not work for a photo, but since the blue is a separate design element you can pick it carefully.

If you have a calibrated monitor and a CMYK profile from the printer you may be able to do without the swatch book.

[D Fosse · Accepted solution]

First of all - you need to know exactly which CMYK. The Photoshop default just happens to be US Web Coated (SWOP), but that may not be the right one. SWOP does not apply, and is not used, outside the Americas.

When you need to push a color to the gamut limits, work by numbers. You need 100% C, and 0% Y and K. Add M to get the right ultramarine hue.

Any more saturated than this is not possible using these profiles and process inks. Then you need spot inks.

[jediavenger]

Thanks all for the information.

I've explained everything to the client and thankfully they understand the colour will need to be different in print

Thanks for your help. James