As the SR-71 had a second cockpit behind the pilot for the RSO, it could not carry the A-12's principal sensor, a single large-focal-length optical camera that sat in the "Q-Bay" behind the A-12's single cockpit. Instead, the SR-71's camera systems could be located either in the fuselage chines or the removable nose/chine section. Wide-area imaging was provided by two of Itek's Operational Objective Cameras, which provided stereo imagery across the width of the flight track, or an Itek Optical Bar Camera, which gave continuous horizon-to horizon coverage. A closer view of the target area was given by the HYCON Technical Objective Camera (TEOC), that could be directed up to 45° left or right of the centerline. Initially, the TEOCs could not match the resolution of the A-12's larger camera, but rapid improvements in both the camera and film improved this performance.