Citizens of the Dutch Republic joined organisations such as guilds for different occupational groups, civic militia, and the administration of charity. And they loved to be painted in group portraits.
Verspronck
The colours you see in paintings today may have faded badly from their originals. Examples of madder lake, smalt and indigo.
Paintings that don’t look like they were intended to be, from Leonardo’s Last Supper, to Manet’s cut-up Execution of Emperor Maximilian.
Fading and colour change in paints has been well-described since 1400. Shown here in examples using indigo, it wasn’t properly investigated until the late 19th century.
When it was first used as a pigment, this vegetable dye proved reliable and lightfast. Later technique, though, resulting in it fading. Why?
The Eclectic Light Company 