Kerschmann usually begins his process with a sample about the size of a pencil eraser. It is stained with fluorescent dyes and embedded in hard black plastic. He then clamps it to his microscope. The scope shoots laser light through the sample, which excites the fluorescent dyes. A digital camera captures the image, and then a blade slices off the sample's outer layer. That layer, which has been damaged by the cutting, is discarded; the rest of the sample, however, remains intact. Next, the sample's freshly exposed layer is imaged; then it too is removed. As this two-part process is repeated over and over, the sample slowly shrinks until there is nothing left of it. What is left, however, are the 1,000 or so images of each of its layers, stored on a computer. A software program compiles them into a single, luxuriously detailed, three-dimensional view of the original sample.