Clearly I am not a professional user. Since Billy thought of Beyonce when I said "curves", it is probably an acceptable starting point for him given it is free.
It is quite possible that he knew the concept, but not the name.
I'm curious to see how much better the 16-bit conversion process works on a low-resolution web photo such as Billy's. Care to submit your version, Doug?
I don't usually spend much time fooling around with other people's images, but just this once for you...
I was able to download the full size original
http://walkinginthewoods.smugmug.com/photos/452041670_7NKcD-O.jpg and the grouseking's small "before"*
http://inlinethumb16.webshots.com/24655/2453352120049158222S600x600Q85.jpg. Both show spikes near the right edge of the histogram as if there was clipping (saturation) followed by some processing (perhaps the creation of the JPEG) which brought the saturated pixels to a lower value. (The brightest part of the image is the sky in the upper left corner--much brighter than anything in the foreground.)
* Grouseking's "before" image is only 48KB (1.6 bits/pixel)--thus it is likely to be damaged by the JPEG conversion. (The original is 3.1 bits/pixel--saved in Fine mode. Fine is the highest quality JPEG available from the XT.) If one expects to post-process a JPEG, one should save it at the highest quality possible (or a quality of 95 or so). Better yet, shoot RAW...
I can easily replicate grouseking's "after" with xv (
http://en.wikipedia.org/wiki/Xv) by simply using a straight-line "curve" from 0,0 to ~220,255 (ie a small brightening of the entire image). One can get a similar brightening of the dark part of Bondcliff with minimal effect on the bright zones by increasing the gamma from 1.0 to 1.1. One can also get a combined effect by pushing the one-quarter to mid-point up a little (ie a 2 straight-line segement "curve"). I can also do essentially the same thing with GIMP, CinePaint in 8 or 16-bit mode, and LightZone (a 16-bit commercial image processor aimed at the professional/semi-pro market
http://www.lightcrafts.com/).
It is clear from the sensitivity of the image to the gamma setting in xv that the appearance of this image is highly sensitive to one's display and its settings. (This is probably true for most high dynamic range images.) I suspect that variation in our displays (most of which are likely uncalbrated) plays a significant factor in our individual opinions and preferences of the images.
After fooling with the image for a bit, I don't think it is a very good one for showing the limitations of 8-bit processing. My website space is very limited, so I didn't bother to save or post my resulting images.
The original image was shot with a Canon XT. If Billy saved a RAW version of the image, it might be more interesting to play with. (But as I stated above, there are probably better images for exploring this issue.)
Doug