CIE ΔE* (Color Difference) Equations

Pictured above is a combination handheld spectrophotometer and densitometer, the SpectroDens 4.  The intent of using deltaE (ΔE) is to describe the distance between two colors. The Just Noticeable Difference (JND) of deltaE is usually 1. In other words, if two colors have a deltaE less than 1 it is imperceptible and larger than 1 is perceivable. Unfortunately, due to the nature of human color perception (our eyes), the visual perception of colors is different….

What is the Process Free (or Processless) Plate and What to Consider When Switching?

Photo Credit: Kodak Sonora Process Free Plates Since the introduction of the CTP (Computer-to-plate) plate from AGFA in 1993, it only took 2 years for more than 50 CTP systems to be brought to the DRUPA exhibition held in 1995. Nowadays, if you walk into a litho offset shop, you will definitely find a CTP system somewhere, usually in a separate CTP room or sharing space within the prepress department. Just like any equipment you…

Five Tips for Creating Your Color Bar

Five Tips for Creating Your Color Bar Evaluate all of your presses so you have complete information on the manufacturer, print width, number of keys, and individual key width. This will allow you to map a color bar that will work for each of your presses. Be sure that each ink zone has at least one solid patch per ink used on press, so you know how to control the keys based on density or…

A simple review of CIE ΔE* (Color Difference) Equations

PHOTO: Techkon SpectroDens 4 all-in-one-color densitometer and spectrophotometer. If you work in the color industry, either you are a brand owner, merchandise designer, printing professional, paint department staff in Home Depot or Lowe’s, or just a complete color geek like me who likes words like CIE CMC color, you will likely hear the term “ΔE”, pronounced “delta-E”. Since I work in the color industry, I spend most of my time talking to all of the…