Michelangelo mixed the pigments in the highest contrast to create consistently realistic luminance, thus producing an artful three dimensionality on a two dimensional canvas. Looking at the images in Livingstone, one print of the original and one of the black and white, it’s really impressive to see how unmistakable and clear the shading is. “Luminance is necessary to perceive depth,” which is clearly what Michelangelo was striving for and accomplished quite successfully. Trying to achieve depth and three dimensionality made me think of Mondrian’s striving for a perfectly flat, two-dimensional image. However, he did seem to use pure colors, which have varied luminance. Brightness distribution over the whole visual field helps to orient objects in space. So a large, bright red section might seem much farther forward than a small blue square underneath it. Also, the local schematic would have impacted the changes in luminance, thus creating the perception of depth.

Our visual systems are able to process thousands of luminance levels with a finite number of excitatory cells. Because of the center/surround organization of the retinal ganglion cells and the thalamic cells, they respond to abrupt changes, in this instance, in changes of luminance. The visual system organizes brighter areas and darker areas in each area of the painting, rather than constructing an entire gradient from the whole visual field. Rembrandt was able to successfully manipulate luminance by creating gradual shifts in the background and using sharp local changes to increase contrast. Similarly, Daddi used luminance changes to enhance the throne, painted in perspective. The alternating lights and darks and highlights make the curvature of the seat perceivable.

Arnheim’s discussion of the location of the light source, either inside or beyond the painting, was interesting. The idea of the objects “becoming enlightened” by way of contact with the light source was really intriguing. Bringing the viewer’s attention to significant objects without throwing off the balance or meaning of a piece can be a tricky process. But in The Holy Family, Rembrandt uses lights and shadows to create a dynamic piece. The “glowing” book seems to make no sense until Joseph’s gigantic shadow lends to the location of the light source. In addition, that the illuminated book and the pale pink cherubs in the top left corner both stand out against dark shadows. Mary’s face is also brighter as it is caught between the reflections of the angels and the (good) book.

I've just finished a painting that I adapted from a black and white photograph. As you all know, a

B &W photograph can have some confusing shadows, especially if you're trying to paint them in color. I too am guilty of undermining the importance of shadows, but I have to say that once I added ( what I thought was going to be a big reddish black mistake) the arm it was on and the microphone it was from seemed to pop! It all came to life and started to look like a real painting.