The ubiquitous Cape Petrel shows its wing patterns off to best effect in sunlight

The luminous qualities of petrels wings are shown as the sunlight shines through the white wing patches on a sunny November afternoon in the Southern Ocean near the South Orkney Islands. Taken with a Canon 7Dii and 100-400mm at 400 mm on 21 November 2015. Exposure was 1/500 sec at f/9.0; ISO 160