Royal family members sit for portraits a lot. And even when they don’t, artists paint them anyway. Some of these portraits have drawn near-unanimous praise and stood the test of time, captivating viewers generations later. Others have attracted mixed reactions, scandal or controversy.

With some artworks, critics objected royals were too gloomy, too naked, or, in the case of King Charles III’s latest portrait, too red.

In the painting unveiled on Tuesday, Charles is enveloped in a cloud of crimson, hot pink and fuchsia.

The artist, Jonathan Yeo, told The New York Times in an interview last month that he got to know his subject over four sittings, beginning in 2021, when Charles was still Prince of Wales, and continuing after the coronation last May.

“Age and experience were suiting him,” Mr. Yeo said. “His demeanor definitely changed after he became king.”

“Life and death and bloodlines and damask. Wonderful,” wrote Jonathan Foyle, a British academic, on social media. But not everyone was as impressed.