How to calculate delta E
Calculating Delta E is crucial for determining the color difference between two colors. This measurement is widely used by industries such as printing, textiles, and manufacturing to ensure that products’ colors are consistent, accurate, and visually appealing. In this article, we will discuss the concept of Delta E and guide you through the process of calculating it accurately.
Understanding Delta E:
Delta E (ΔE) is a numerical representation of the difference between two colors in a defined color space. It is based on the color model (such as CIELAB or CIEDE2000) where both colors are defined. A lower Delta E value indicates a smaller color difference, while a higher value signifies vast differences between the two colors.
Step 1: Choose a Color Space:
Before calculating Delta E, it’s essential to choose a color space that best represents your needs. The most common one used for this purpose is the CIELAB color space. Other options include CIEDE2000 and CIE94.
Step 2: Obtain Color Values:
After choosing a color space, you will need to obtain the Lab values (L*, a*, b*) for each color you want to calculate. The L* value represents lightness, while the a* and b* values signify chromatic coordinates.
Step 3: Calculate Delta E:
As mentioned above, different models can be used to calculate Delta E; we will now outline steps for calculating it using both CIELAB and CIEDE2000.
CIELAB – Calculate ΔE*ab:
1. Find the difference in L* (ΔL*) by subtracting L*_1 from L*_2.
2. Find the difference in a* (Δa*) by subtracting a*_1 from a*_2.
3. Find the difference in b* (Δb*) by subtracting b*_1 from b*_2.
4. Calculate ΔE*ab using the following formula: ΔE*ab = √(ΔL*^2 + Δa*^2 + Δb*^2)
CIEDE2000 – Calculate ΔE*00:
Calculating ΔE*00 is more complex, involving multiple equations and factors. The general steps include calculating differences in lightness, chromaticity, and hue angle, followed by a series of equations to determine the final value of Delta E. For detailed instructions on using CIEDE2000, refer to its official documentation or use online tools.
Conclusion:
Calculating Delta E is an essential task for measuring color differences and ensuring color accuracy across various industries. By following the steps outlined in this article and choosing the appropriate color space, you can achieve precise and reliable Delta E measurements.