The reclosable dust cover on Curiosity's Mars Hand Lens Imager (MAHLI) was opened for the first time during the 33rd Martian day, or sol, of the rover's mission on Mars (Sept. 8, 2012), enabling MAHLI to take this image.
The level of detail apparent in the image shows that haziness in earlier MAHLI images since landing was due to dust that had settled on the dust cover during the landing.
The patch of ground shown is about 34 inches (86 centimeters) across. The size of the largest pebble, near the bottom of the image, is about 3 inches (8 centimeters). Notice that the ground immediately around that pebble has less dust visible (more gravel exposed) than in other parts of the image. The presence of the pebble may have affected the wind in a way that preferentially removes dust from the surface around it.