Related density maps can be compared by morphing from one to the other. Several intermediate maps are generated by interpolating between the starting and ending maps. The morph can be viewed interactively and recorded as a movie. The contour level can be adjusted automatically to keep the enclosed volume constant throughout the morph, and other aspects of map display can be adjusted with Volume Viewer.

The image shows the structure of the human TRPA1 ion channel (wasabi receptor) determined by electron cryo-microscopy, Protein Data Bank entry 3j9p. The four subunits of the tetramer are shown as ribbons in different colors over a dark-to-light gradient background. (More samples...)