The Sunlight Test

Artists are passionate about color, and so is Winsor & Newton. That’s why they’ve created the Professional Acrylic line of paints, which is tested to ensure that their bright, vibrant hues remain perfectly consistent and will last for years.

This striking spectrum of color doesn’t happen by chance. Instead, the dependable and stable hues are the result of rigorous testing performed by a team of chemists in their London laboratory. You can explore the process through this behind-the-scenes footage.

The tests begin with an applicator bar drawing the paint across the full length of the chart card at a constant speed, delivering an even level of thickness. This ensures that the opacity is perfectly consistent.

Winsor & Newton’s opacity testing machine.

Vibrancy can change during storage, which is why the second test is meant to ensure that the paint maintains its color strength for up to five years after purchase. The paint is incubated at extreme temperatures in a Color Stability machine in order to test its resilience.

Once you’ve created an artwork with paint, it’s important that the colors continue to perform over time. Using a carefully calibrated piece of technology known as the Sunlight Machine, which exposes the paint to UV light, the light fastness of Winsor & Newton’s Professional Acrylic paint is put to the test. By emulating the passage of time this way, the paints can be guaranteed to have up to 100 years of colorfastness.

These thorough tests are just one way that Winsor & Newton is dedicated to ensuring their Professional Acrylic paints perform to the highest possible standard, and delivering on their ambition to provide artists with  the best possible materials.

Learn more about Winsor & Newton’s testing process and Professional Acrylic Paints at

This post was sponsored by Winsor & Newton.