Reconstruction of fine structures of plant organelles can not be done
applying light microscopy. The resolution of this technique is too poo
r, therefore Transmission Electron Microscopy (TEM) has to be used. Ho
wever, it is impossible to evaluate larger parts of the cells or whole
cell organelles because specimens are too thin for these topics. This
is also the reason why computer-tomography is impossible. Therefore s
eries of ultra-thin-sections were used. Black and white images of TEM-
preparations were transformed into pixel-images with a scanner for fur
ther analysis with a computer. After this procedure the images were tr
ansformed into vector-graphs. Now it was possible to reconstruct organ
elles in a 3D view and to calculate areas and volumes. Illuminated spi
nach leaves were used as objects for evaluation. The results of the 3D
reconstruction of spinach chloroplasts with their ultrastructures and
the calculations of the volumes of their components are shown in this
paper.