A technique for collecting spatially resolved optical emission from large rf plasma reactors is described. To demonstrate the sensitivity and versatility of this technique, emission within the quartz ultraviolet, 225-253 nm, was studied with particular emphasis on the "plasma dark space." Spatial variations of CF2, AlF, and C atom emission were monitored. These results have been used for discussion and evaluation of various plasma excitation and reaction mechanisms involving atomic carbon in fluorocarbon plasmas. © 1985 Plenum Publishing Corporation.