I tried the process the Slough suggested using a shadow and a highlight output from RAW and Color Range to generate selections>mask and got good results for an image that I've been fighting with in a more conventional way.. I was thrilled to arrive at something halfway decent in about a half an hour or so...sheesh. I think you have to stay subtle with this trick or things start looking funny.
Cool to be able to find quite a bit of control in a short period of time. The image was exposed to hold the brightest part of the sky, basically, the sun behind a fairly thin layer of clouds. Im hoping to find some time tonight to try all the other stuff in this thread. Sarah? Does your plug-in work on a mac? is it just a simple PS plug in?
The plugin currently is Windows-only. Hopefully a volunteer will come along to port it, but more work is needed on the original first -- currently it works very well on Megavision images, pretty well on Better Light images, and not that well on everything else, so it needs tweaking based on some different source material. Basically, if there isn't that much fine detail at the pixel level, it is a bit too aggressive with its smoothing. The Megavision images have at least 2 to 4 times as much pixel-level detail as each colour plane of an image from a Bayer sensor, so I need to do some changes to accommodate that difference. I should be able to iron this out given a bit of messing around time, hopefully this weekend. I'll also add some shadow/midtone/highlight settings so you can back off the level on mid tones and increase it in the shadows, which should also help.