Describing Color

[bfcreativenyc1]

Hi,

I'm working on a project where someone is trying to a selection of printed CMYK colors as close as possible to a selection of PMS colors, and asking me to tell them if they are accurate.

However, I'm not sure that my vocabulary is correct. There are two examples I'm wondering about:

1.) PMS Warm Red

-They have given me color options that don't feel bright enough, but I don't know that that is a good enough description. For example, one of the options they gave was 0/82/90/0. The CMYK equivalent of PMS Warm Red is 0/87/80/0. So, in theory, if you decrease the Magenta and increase the Yellow you should get the same color.

-Would that be the way to describe the change? "Add Magenta and Decrease Yellow"? Or would it be to make it brighter or something else? If its helpful, I would say the Warm Red C looks more pink as well.

2.) PMS 137 C

-They've given me options which are much closer to PMS 136 C. The CMYK for PMS 137 C is 0/42/100/0 and PMS 136 is 0/28/86/0.

-PMS 136 feels like a darker shade than PMS 137, and possibly more saturated.

-Is that an acceptable way to describe how to change it? "Make it a shade darker and increase the saturation"? Something else.

Thanks! 

[MichaelStephens]

The person printing the colors really shouldn’t need to ask you if the colors are correct. Pantone already has defined CMYK color breaks for printing CMYK colors close to their PMS equivalents. If they’re measuring out the color according to the breaks Pantone has specified then the color will be as accurate as it can be in CMYK. If they’re not sure they need to have a Pantone color book to compare their printed items against.

When it comes to color mixing, you can’t tell someone to add or remove a color for a few reasons.

1. “Adding more yellow” is arbitrary as there isn’t a corresponding measurement. How much more should they add. You also can’t decrease color that’s been mixed, you would actually have to add more of the other colors.
2. Mixing colors is done by using a precise combination of ink weight. If you’re just randomly adding more color to the mix to get the color you’re after, you’ll have an even worse time trying to match it if you have to make another mix. Since you don’t have anything that informs you how much of each color you’ve used when trying to get the “right” color, you’ll have no way of knowing how to get that exact same color again next time.

[bfcreativenyc1]

Thanks for your reply Michael.

They're asking because we're a client and need to approve it because we want to start getting closer than we have in the past. The problem is The Pantone defined CMYK equivalents are rarely accurate to the PMS colors when printed.

[Monika Gause]

bfcreativenyc1 schrieb:

The problem is The Pantone defined CMYK equivalents are rarely accurate to the PMS colors when printed.

That's why nowadays they include Lab numbers instead of CMYK. And then let color management do the job.

The CMYK numbers are hardwired to a certain printing process, paper and even ink. You only need to print in a different country, use inkjet instead of a printing press, and the CMYK numbers won't be appropriate at all.

[MichaelStephens]

It's not specifically because of accuracy but because you can't reproduce the colors with CMYK. The best you can really hope for it to find something that's close.

A question I do have about the print job. Is CMYK necessary, such as for photos, and to then have the actual spot colors would make the job more than 4 colors thus increasing the cost of the run?