The harmonic relationship of certain chemical species is exploited to produce an MRI image of a single chemical species in the presence of at least two other chemical species with the acquisition of as few as two NMR images. If the chemical shift frequencies at a particular polarizing field strength can be approximated as the ratio of two odd integers, an evolution time can be chosen for the images acquired to cancel the contributions of two of the species in one image with a corresponding contribution in the other image. A image of the uncanceled species or of the cancelled species alone may be generated. A third image may be used to correct for inhomogeneities in the polarizing B.sub.0 field.