Best color question for gray backgrounds?
The best color in a book is something that all designers and self-publishers want. The title question is asked recently by a book designer about the best way to create two gray colors for backgrounds. Let’s first assume that you have accurate color on your monitor.
The question …
I understand that I will be converting all images to the US Sheetfed Coated v2 profile. I want to define two background colors as dark gray and light gray.
When I build the InDesign layout, will I get better book printing results by defining backgrounds as a percentage of black, or converting the values to CMYK in Photoshop? How will I get the best color?
Our answer …
First of all, we always work with CMYK for full color book printing, not RGB, or even Lab colors.
Secondly, you cannot get the same result when converting from RGB to CMYK. Converting RGB to CMYK happens automatically when you are in Photoshop. To do this, select Edit from the menu, and then select Convert to Profile. Choose US Sheetfed Coated v2 or Uncoated, that is, if you are printing with Star Print Brokers. However, black and white images do not be converted. This also depends on how we quoted your job. So, check your quote, or just ask us.
However, be aware that there may be a problem with the result when choosing between CMYK or a black ink percentage.
Using CMYK or defining a black ink percentage.
Do you want a halftone look or a process color rosette?
Are you pulling ink from just the black ink tray on a press, or from all four inks that make up process CMYK? If it is just from black, you will have in essence, a halftone, when chose a percentage. For the dark and light grey background, this might be 80 percent and 15 percent. If you pull from process CMYK, you will have the process color rosette instead of a halftone look. Either can create the best color that you are looking for, but the results are different. It is a matter of preference when deciding on great color for your design.
The results between RGB as seen on screen, and CMYK when printed on press, can be very different. There is no way around this, other than making the page of every book a monitor, as in a computer, iPad or smart phone screen.
A note about RGB.
RGB is meant to be viewed on a screen and it has a wider array of color than CMYK. This is because CMYK breaks down color to the four inks used for process color printing. This essentially dumbs down the color. Printing RGB images won’t work either. It won’t provide the best color.
A word of advice about getting the best color.
My feeling is that if I want color I can count on, I don’t play around with mixing my own CMYK values. Instead, I go to our Pantone physical library of swatch books for print. Pantone changes it’s Color Bridge swatch deck in 2023. The new Pantone Color Bridge is $207. I used the coated version. If you are using the previous version, notice the Pantone CMYK call-outs below each swatch. Use their call-outs that should match the process color.
We have the entire library. So, whether it is spot or process, coated or uncoated, pastel or metallic, I can view a color swatch that I can count on, versus guessing.
Use “spot” or “process” to achieve your best color.
It is really a personal choice! The other thing to consider is using a spot Pantone ink for your gray, versus a screenbuild out of process CMYK. This adds another ink — or two in this case — to the press.
Be aware that this means instead of a four-color job, the book becomes a five or six-color job on press. This increases the book printing quote significantly.
The maximum number of inks on the most usual presses used for sheet fed book printing is six inks. This is because they have six trays of ink. The six tray for this job consists of C, M, Y, K, plus one spot light gray, plus one spot dark gray.
Also read out article about resolution and effective resolution, which is part of reproduction for best color and results.
This is a lot to consider for the average self-publisher. But, not to worry. Star Print Brokers is just a phone call or email away. We are happy to help our self-publishers and book designers.