Apparatus for obtaining images of the wall of a borehole, comprises a tool body; a light source mounted on the tool body and arranged to illuminate the borehole wall; a camera mounted in the tool body; and a mirror moveably mounted on the tool body and spaced axially from the camera and arranged to reflect an image of the borehole wall at the camera, wherein the movement of the mirror allows images of different parts of the borehole wall to be reflected at the camera.