These two snaps are clicked almost at same time. (From 4th floor of our company building.) I was almost 8.00 in the evening. I just changed the aperture settings of the camera but sutter speed was same for both snaps. For the dark snap aperture was least open (8.0), so eventhough shutter was open for long time the amount of light entered thru camera lense is less as comapred to settings for brighter image(2.7).

Settings for Some what Dark Image:
Shooting Date/Time 2006:Jun:15 8:00:07 PM
Tv (Shutter Speed) 15
Av (Aperture Value) 8.0
ISO Speed 50
White Balance Auto
AF Mode Single AF
Drive Mode Single-frame shooting

Settings for Bright Image:
Shooting Date/Time 2006:Jun:15 7:59:15 PM
Tv (Shutter Speed) 15
Av (Aperture Value) 2.7
White Balance Auto
AF Mode Single AF
Drive Mode Single-frame shooting