I published my discovery of Vermeer’s use of two mirrors in The Artist Magazine in Jan.1980. (British Version) under the title “Vermeer’s Method of Observation”. Looking at his The Artist in his Studio, sometimes called Ars Pictoria I asked myself the question “how did Vermeer see himself in back view?” Two mirrors seemed the obvious answer. When I carried out the experiment to see if this was true I realized that this was his general method and this, one of his last paintings, was a cryptic description of that method. Very many of his paintings contain an area of painted cloth in the left or right foreground where his own head would normally be reflected in the mirror on his easel. The cloth substitutes for his own reflection. The second mirror has to be bigger and placed about a meter and a half behind him.
More recently (July 2011) I placed two films on Youtube where Anne Shingleton demonstrates how helpful the system is. The chief benefit is the fact that the loss of light, particularly in a 17thC mirror which uses silver not mercury as the reflector, reduces the image down to a point where light can be matched with pigment. In July 2012 I put up a third film pointing out the improbability of his use of the camera obscura as a general method. In my view he was primarily interested in light, and to observe unfocused light he was obliged to use the camera obscura, as the eye refocuses automatically.
I am delighted to see that Tim Jenison has reopened the debate but am not convinced that his explanation of Vermeer’s unique genius in judging colour and tone is better than mine. Mine is simpler and accords with the evidence in many of the paintings (particularly Ars Pictoria). Probably most important it affords Vermeer a panoramic view of the subject and the reduced image of it after bouncing twice in 17thC mirrors thus allowing him to match light with pigment. This is the crux of Vermeer’s success in painting light.
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