Maybe its a coincidence that Canon's slogan 'Delighting you always' the word D-Lighting or Dynamic Lighting is used by Nikon. Canon's version of D-Lighting is called.. Highlight Tone Priority.. which only has one setting 'Enable' unlike Nikon which has 3 different modes of different strength to cater for everyone's fancy.
Anyway this post isn't about Nikon vs Canon but rather the usefulness of such technology. Cameras such as D80 which DLighting first made its appearance even if its in a passive way as compared to the Active DLighting with the D3,D300,D700 and the newly announced D90.
What does DLighting do?
DLighting is best seen in high contrast scenes, meaning you have really bright areas and not so bright areas. Like the picture shown below. The sky is bright and the trees in the foreground isn't as bright hence it looks like a silhouette. But wait a minute, that's not what my naked eye see is it?
Well those brains at Nikon knew that there are limitations in going digital as compared to those good and expensive film days hence they came out with DLighting. DLighting brings out those dark areas and tone down any of those bright areas (highlights). What you get is more what the eye see which is shown below. The picture is applied using DLighting mode Normal.
Now doesn't that look way better? At least its an accurate representation of what the scene actually looks like.
Its extremely useful when you have to take the sky such as sunsets and landscapes. That's the power of DLighting right there.