Who knows why, but I converted a lunchtime shot from Heybridge Basin in Essex to appear as dusk using Lightroom 3.
I am learning how to use it by messing about rather than read up. Original shot with Canon 5D

The original shot converted to dusk by petach123 (Peter Tachauer), on Flickr
Conversion

From day to dusk by petach123 (Peter Tachauer), on Flickr
I am learning how to use it by messing about rather than read up. Original shot with Canon 5D

The original shot converted to dusk by petach123 (Peter Tachauer), on Flickr
Conversion

From day to dusk by petach123 (Peter Tachauer), on Flickr