A spectrophotometer reads lightness, red-green and yellow-blue values of a coated part and the standard panel, and delta E combines the differences into one figure. A delta E around 1 is about the smallest difference most people notice side by side, and architectural specs often cap batch-to-batch variation near that. Readings shift with gloss, film build and cure, so panels are read in the same conditions.
Delta E is 2.3 against the standard, mostly in the yellow, I think the oven's overbaking.
Also heard as
- dE
- color difference
Related terms
Gloss
How mirror-like a finish is, read with a gloss meter at a fixed angle, usually 60 degrees.
Overbake
Cure that went too hot or too long, causing yellowing, gloss loss and brittle film.
Bonded metallic
Metallic powder in which the flake is fused onto the base particles so it sprays and recycles evenly.
AAMA 2604
The mid-tier North American architectural coating spec, requiring five years of Florida exposure with limited fade.