Planar Scenes, Color Images, and Variation of the Camera Aperture

These sequences contain images taken in the same conditions (as far as we could control the environement parameters), but the camera aperture which varies slowly from one image of a sequence to the next one.

Image of a city.

See the whole sequence , download it (tar of gzipped PPM images).
Sequence reference: c2_ip_ap_s1
Images: im1 to im12 from darker to lighter (8 of them are shown here)
Scene: Image of a city.