Unlike Pixillation, UFOs doesn't rely on a juxtaposition of machinic and hand-done animation. Instead, the shapes generated by the computer are even more fused with color, and entirely black frames were inserted. With UFOs, accompanied by music of Emmanuel Ghent, Lillian Schwartz started experimenting with stroboscopic effects—known to experimental cinema as "flicker". In the way Schwartz used pure color, she also pushed 2D to look 3D when being watched with ChromaDepth glasses. Because the glasses are prismatic, differences in color within the film naturally engender a layering of depth.
"UFOs proves that computer animation—once a rickety and gimmicky device—is now progressing to the state of an art. The complexity of design and movement, the speed and rhythm, the richness of form and motion, coupled with stroboscopic effects is unsettling." (Amos Vogel)