Index 385 2x extenders, 137, 138f 3d production camera equipment, 97f editing in, 348 shooting, 168 shot selection, 67 stereographers, 20 3dtV, 340­341, 341f defined, 329 possible health risks, 342 4k cameras, 98f 180 line. See Action line Aspect ratios 4:3, 174f, 296, 297f, 298f, 322, 322f 16:9, 174f, 296, 297f, 298f, 322, 322f defined, 291 Assistant directors (associate directors; Ads), 15­16 Assistant producers (associate producers; APs) control room layout, 22f job description, 14 Audience surround sound, 245­247 wireless, 247­248 mono sound, 233­234 nature of sound, 231 overview, 230­231 stereo sound, 234 surround sound, 235 Audio assistants (boom operators), 20, 20f, 116 Audio filters, 256 defined, 229, 230 Audio input sockets, 116 Audio mixers (device), 251­252,