We capture a picture of each section using a digital camera mounted on a microscope. Each section is brought into the field of view, lined up with the previous section (red) then saved onto the computer hard disk. The picture below shows a view of the program we use for that task. These pictures are stacked on top of one another to make the reconstructed model. So that the reconstruction of the 3D picture is easier the image values (grey-levels) in each picture have to be corrected so that the background values are uniform, this is known as shade correction