When plotting different orbitals with consistent contour values, one can create illusions about the relative extension of charge distributions. We suggest that the comparison is not biased when plots reproduce the same fraction of the total charge. We have developed an algorithm and software that facilitate this type of visualization. We propose superimposing molecules and associated orbitais, and creating cross-sections by selecting a particular part of the orbital limited by pre-defined planes. © 2008 American Chemical Society.