Color is a funny thing. You'd think, by its nature, that it would be 'black & white'. And it is. Kind of.
But in the world of commercial printing, black isn't always black and there are multiple ways of achieving black. And white? Well, that depends on what material you're printing on.
Sound complicated? Well it is. And it's not at the same time.
The biggest recommendation we can make is simply to have a conversation with your printer. Speak with their prepress department and explain what you are trying to achieve. While the theory behind what we are all doing is pretty much the same, we all use different equipment with different profiles—different calibrations and preferences—and have different workflow and processes that may necessitate one approach over another.
Therefore, communication is probably the most important part. And, if possible, as early in the design process as you can. Achieving color may include providing a sample, or swatch of what you have in mind. This could be a color target that is actually used on press. Or, the sample could just be a visual reference that tells everyone involved that this is what the desired output should look like.
If you've created a custom CMYK blend, what you are trying to achieve may not be clear. AND, the reason why you created that custom CMYK blend in the first place may not have been the right approach to achieving that color in print.
I recall working on a new product launch with a client that we have been doing business with for a long time and have a great relationship with (that always helps). And we all knew that this 'burgundy' was an integral part of the product branding. The color was prominently featured on many of the product launch materials. Those materials included some offset printed collateral on a certain paper stock, along with some shorter-run, digitally printed pieces as well as some promotional products. Additionally, the 'feature' piece was a kit made of craft cardboard that would ultimately be wrapped with printed material.
As we do with all of our print programs, we began by doing proofs to ensure consistency of color throughout all the different pieces. Fortunately, these proofs brought to light some confusion with the burgundy. Ultimately, what we realized was that no one was really sure just what we were trying to achieve. Was it that 'rusty' burgundy? Or was it that 'purple-ish' burgundy? We didn't know, and we didn't have a target to use as a visual reference. And, in this example, we were working with a custom CMYK blend of color that had been provided in some initial files and in a client-supplied style guide.
So let's talk for a minute about why someone would want to create a custom CMYK blend.
When choosing color in print design, you make your color selection using a PMS (Pantone Matching System®) book. If you're using a "Color Bridge" book (recommended), you would most likely make your PMS color selection from the left column. This represents the solid, or "spot", PMS color. This means that the printer would either mix that ink color using a precise color formula (similar to how you have a paint color made at the hardware store), or purchase that pre-mixed color from an ink company. Either way, this ensures that precise color will always look the same and be consistent.
But often times the decision is made to print without a solid PMS color.
If you look to the right column of the Color Bridge book, you'll see the CMYK (it may also say 'process') version of the desired PMS color. This column is meant to represent what the color will look like when it is printed using CMYK only. In other words, when the color is produced from percentages of Cyan, Magenta, Yellow and Black vs. being run as a spot color (as described above). Without getting too technical, with some colors, there can be a significant difference between what the spot color looks like and the CMYK (process) equivalent. This is the primary reason why someone would choose to create a custom CMYK blend. Often, they are simply trying to achieve a process color that is more desirable.
But doing this on your own is dangerous!
Why? Because what most designers will do is start adjusting their CMYK sliders within their layout program. They'll use their monitor as the visual reference to make a new color selection. I won't get in to detail on why this is problematic (if interested, see previous blog post 'Understanding Color—in Print'), let's just say that you cannot use your monitor to make color selections with the expectation that you will achieve that color in print. You are dealing with different color spaces, different calibrations, software, profiles etc…
Today's graphic designer has changed. The reality is that most are rooted in the digital space. And there is nothing wrong with that at all. Just understand that the print environment and workflow is different. If you are designing for print, the best thing you can do is to talk to your printer. Let your printer provide guidance in color selection, file creation as well as set the proper expectations to help make your vision a reality.