Usually you take take an image at a low, normal and high exposure setting, but for these tests, I simply post-altered (in Picasa) an existing photo from an overcast drab day from last year's fly in (actually Robs, AvidFlyer and my first trip to Mile Hi). You can add fill light or darken and then export the photo very simply.
The tests are overly stylized - almost painting like. You can reduce the dramaticness of the effects to give a more realistic look. I will play with that some, but there are possibilities to get some really cool images - especially on dark days with poor light/haze.
Here are the results:
Original Image:
HDR Processed Image:

Original Image:
HDR Processed Image:

Pops Original Image:
Pops in HDR!:


















