A 3D camera for determining distances to regions in a scene wherein gating or modulating apparatus for the 3D camera is incorporated on a photosurface of the camera on which light detectors of the camera are also situated. Each pixel in the photosurface may include its own pixel circuit for gating the pixel on or off or for modulating the sensitivity of the pixel to incident light. The circuit may comprise at least one amplifier inside the pixel, at least one feedback capacitor separate from the light sensitive element and connected between the input and output of each of the at least one amplifier, and at least one controllable connection through which current flows from the light sensitive element into the input of the at least one amplifier. The 3D camera may further include a light source and a controller.