Printing CMYK Grayscale

[morganp40708669]

Hi! I am trying to print something that uses grayscale colors, my understanding is that rich black should be cmyk 60,40,40,100 but what formulas should I use for the grays? For example, should I use a 0,0,0,50 for a mid gray or would that not match without color in it? On the other hand, would a 30,40,40,50 print as a color?

I want it to be completely unsaturated but include rich black, let me know if you all have a strategy for this thank you!!

[Monika Gause]

Maybe you could show the design?

You have to watch that you get sufficient contrast into it.

And how will it be printed?

[Ton Frederiks]

It will be difficult to find the correct CMYK mix to get a neutral grey. Your 30,40,40,50 mix is probably resulting in a brownish grey.

When you know the printing process/paper and have an ICC output profile for that process, you could use that to convert neutral RGB greys to CMYK.

[Jacob Bugge]

Morgan,

"Hi! I am trying to print something that uses grayscale colors,"

The best kind of greys rather depends on whether you are striving for neutral greys througout the artwork, or use greys along with other colours.

The best solution may also depend on which printer/printer service you are using, as Monika said..

Up to the saturation corresponding to 100K, you get actual grayscale by only using K, such as your 0,0,0,50, so that is safer for consistency; and it is also cheaper for more than one reason, one being the use of only one ink, another being that K is by far the most saturated colour..

But if you go beyond the saturation corresponding to 100 K and need CMY addition for that, it is better to have CMY additions for paler greys as well for consistency: it is more important to have a consistent appearance throughout than to have an accurate specific colour tone somewhere in the transition.

For neutral greys, I like the suggestion by Ton.

It is quite different if you use the greys with one or more other colours, and in those cases I would (normally) suggest greys/blacks akin to the (most important) other colour(s).

For coloured greys, you could use an adapted version of the suggestion by Ton, starting with an important colour represented in RGB, then (also) using HSB to keep the hue.

"my understanding is that rich black should be cmyk 60,40,40,100"

As I see it (literally), there is no right rich black for all purposes.

[Ton Frederiks]

"my understanding is that rich black should be cmyk 60,40,40,100"

As I see it (literally), there is no right rich black for all purposes.

By @Jacob Bugge

There is no fixed rich black as Jacob mentioned. The darkest black can be achieved by converting an RGB black (0/0/0) to CMYK using the correct printing profile. This will avoid exceeding the ink limit for that printing process.