The five images are all shot using a tripod mounted camera looking at exactly the same scene. The images from top to bottom are 1 stop over exposed, 1/2 stop over, correct exposure by the camera meter, 1/2 stop under and finally 1 stop under.
We are affecting the brightness of the image here. The first image is very pale and washed out but notice how the colour gains 'weight' as it gets darker. The fifth image is very dark, perhaps a little to much.
To confirm that it is indeed the brightness that is changing, I loaded the five images into Photoshop and used the info pallet set to HSB to measure the values at the same spot (as close as possible) on each picture. It was the brightness value that reduced on each consecutive image.
