Apocalypse

I took this photo almost one year ago. Initially I didn't like it but when I was going through the older photos yesterday I thought that it looks sort of cool. The sky was really dramatic, it looked as if some nasty storm was approaching.

Technical details:
Camera: Canon 50D
Lens: Canon 10-22 f/3.5-4.5 USM
Focal length: 10 mm
Aperture: f/16.0
Exposure time: 1/200
ISO: 100
Number of exposures: 5
E.V. Step: 2
Flash used: no
Tripod: yes
Filters: no
Software: Magic Lantern 2.3, Photomatix Pro 4.2.5, Lightroom 4.2, Photoshop CS6