Green Lion Arcadian Blue Skies
|Colour Wheel Violet||8000FF||128||255|
|French Ultramarine Blue||120A8F||18||10||143|
|International Klein Blue||002FA7||47||167|
Visible blue light has a wavelength of about 475 nm. Blue wavelengths are shorter than over wavelengths of visible light. When they are scattered by the molecules in full daylight, they give the sky a blue appearance.
The blue seen in nature, is fleeting: it is a colour always difficult to tackle in art or design. Sources of blue for the medieval artist were dyestuffs: woad and indigo. The blues of Marketplace at Leominster by John Varley (1778-1842) created with indigo dye have faded as have the colours of many other 18th and 19th century watercolours. George Field (1777-1854) in his "Field's Chromatography or Treatise on Colours and Pigments as Used by Artists" remarked upon how:
"Blue pigments, like blue flowers, are more rare than those of the other primary colours. In permanent blues the palette is very deficient, the list being exhausted when the native and artificial ultramarines and the cobalts have been mentioned. That there is room for new blues, durable and distinct, cannot therefore be denied."
The cobalt blue and French ultramarine blue pigments used by the Impressionist group of painters have proved more durable.
Blue Light Conditions