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A Color Conundrum: Accurate but wrong.
Recently while perusing my local wing joints sauce heat index I started thinking about an all too common problem for printers. How spicy is too spicy? Color perception, like taste is very subjective.
I grew up with an Asian influence in a step-mother who immigrated from South Korea. I enjoy very spicy foods. My wife on the other hand grew up with a comparably “bland” palate. Thus food she finds too hot I regularly enjoy. Similarly when discussing color do we know how “spicy” our customers want their color?
Generally when discussions about color or color accuracy come up they usually center on industry specifications, calibration methods or how close to a particular technology or media can achieve to some other technology. These are important topics that speak to consistency and accuracy, what’s usually missing is what does the customer expect to see? A press can print 100% accurate and still be 100% wrong to the end customer. How is that possible?
When measuring spiciness something called the Scoville scale is used which defines the pungency (spicy heat) of chili peppers. However this scale lacks any relationship to how “hot” is too hot for someone’s palate.
For example if asked “Do you wish your soup to achieve a Scoville rating of 20,000?” or “Do you want some jalapeño peppers in your soup?” Which question will more accurately communicate acceptable spiciness than the other? I’m guessing the latter, but why?
When communicating subjective topics there has to be a common experience between all parties in the conversation. All parties had to have an experience of a jalapeño peppers spiciness to have a common point of reference. From that experience a language of acceptability can be understood.
The same is true of color perception. In printing when describing how close two colors are we generally use a term called Delta-E or Delta Empfindung; German for "sensation". Delta-E is the scientifically measured difference or distance between two colors. However this number does not accurately reflect how much we like a color.
If asked “Does a 3 Delta-E difference meet your color expectations?” or “Is this color warm enough for you?” which question better reflects how most end users experience or communicate color?
There is an additional challenge for color perception. While we experience color every day we don’t experience it the same or have to communicate that experience constantly. Case in point: In many of my color training classes I ask my students what is the color of a ripe banana? While the question is specific the resulting answers vary wildly. What is ripe to you? How much brown is unacceptable? Is ripe the point you can eat a banana or the point where any more ripening and it will have to go into a banana nut bread or the trash? These differences in how we perceive ripe can have a drastic impact on the perception of the color for ripe banana yellow.
Similarly how warm is warm enough for a specific color. Does a little warmer mean 5% magenta or 10%? How do we know what the customer really wants?
Building a common language is not difficult if we use of some simple tools and techniques.
The most important tool that we use to communicate color is light. Without light the conversation around color goes dark. ‘Pun’ intended. All the colors we see is in the lighting environment we are in. Use of a standard industry lighting environment is critical to this conversation. There are many commercially available D50 or 5000K light boxes and booths but if you don’t have access to one then go outside around noon. While not perfect, it sure beats those florescent tubes over most desks.
A tint book is the next tool that will help to quickly discover the color a customer wants. Generally speaking a tint book will be a set of swatches in different stepped CMYK percentages printed using the press and paper the customer will use. Some tint books range through the entire gamut possible. These books can be a couple hundred pages in size and may be cumbersome. Some tint books are a small segments in the color families that are important to the end user. Key to success is the books are printed with proper calibration and color management on the press with the paper the customer will use for their job.
Industry swatch books are also useful especially when working with a global brand. However pay particular attention to the substrate and printing process used to create these swatch books. If the workflow, process and substrates differ then the color values in these guides are not always applicable to the print.
For example if the color the customer likes is the solid swatch printed on a glossy coated media but the job is printing CMYK inkjet on a book stock then the swatch is not an accurate target. This is where the tint book is needed to find the closest acceptable color for the technology and media being used.
Finally remove vague descriptors from the conversation. This may be more difficult for old-school traditional printers. Using terms like pop, warmer, cooler or shift the neutrals less green can cause the uninitiated to be left in the dark.
In today’s digital world this archaic way of describing color is becoming a lost art form. So we must look to more digital ways of describing color. Use tools like the tint book and ask does this swatch match your expectations?
If we consistently implement these few steps and tools with our customers we can quickly learn just how spicy they like their color.
Jan Lemieux is Advisor, Color Solutions Engineering at Canon Solutions America. A key member of Canon Solutions America's team of color experts, he uses his 23 years of high-end commercial offset printing experience to help fast-track customers into digital color printing. He is an IDEAlliance G7 Expert and Color Management Professional Master (CMP Master).