When the highlights are much brighter than the shadows the trouble for photographers in capturing these scenes are on their highest level. There are a lot of technical advices and measurements to validate these scenes but most of them are unimportant for the practical photographer.
The important factors are: brightness, lightness, luminance and reflectance.
At what point does a scene quality as HDR? When should you consider taking a HDR image and tonemapping it?
Nowadays it seems to be a matter of taste and opinion, there is a fashion for giving extreme tonemapping treatment to images that don’t need it, simply for getting an unusual effect. For me it is part of testing different settings and different kind of software to get a result how I have seen and experienced the scene. Sometimes it works, sometimes it doesn't.
When I have been in Dresden it has been a rainy and overcast day in late afternoon with the last lights of the sun iluminating the scenery. I saw the buildings right before me and could clearly see the windows, doors and little other things. When I tried to capture it in camera either the sky was totally blank and washed out or the buildings have been nearly dark. A typical situation to photograph in different exposures and to try to bring them together at a later stage in software.
The first image I took looked like this:
Apart from using a wide angle lens and a bad viewpoint which has a lot of distortion in these shot it was nearly the best which I could get from my small point and shoot like device. I decided to take to more pictures with different settings.
Bringing all togehter and tonemapping it in CS 5 I could see that there would be a potentially better image like I had seen it at that day. As I didn't have a high quality RAW file but thought it interesting to show what possibility even on a rainy day HDR processing offers I opted to show the images as an example of the immense ranges we can capture with these technique.