This image was acquired to look for frost on these generally equator-facing slopes, which are visible in the shadows after enhancing the brightness levels. It is also a dramatic image given the low-sun illumination.
The color cutout has north down (illumination from the right side) so that downhill is down .
Written by: Alfred McEwen (audio: Tre Gibbs) (20 April 2016)
More info and image formats at http://hirise.lpl.arizona.edu/ESP_044514_1315
Image: NASA/JPL/University of Arizona