On Sol 32 (Sept. 7, 2012) the Curiosity rover used a camera located on its arm to obtain this self portrait. The image of the top of Curiosity's Remote Sensing Mast, showing the Mastcam and Chemcam cameras, was acquired by the Mars Hand Lens Imager (MAHLI). The angle of the frame reflects the position of the MAHLI camera on the arm when the image was taken. The image was acquired while MAHLI's clear dust cover was closed.
The image was taken on a day when MAHLI and other instruments and tools on the turret were being inspected using the rover's Mastcams and Navcams. The MAHLI cover was in the closed position in order to inspect the dust cover to ensure that the cover, its hinge, and the volume it sweeps when it opens are clear of debris.