I'm doing this partly because Jeroen asked about my BW processing on Flickr. And I always do what I'm told by clever people...
I've been playing with PP in CS5 (in-between house-painting) this week, and it has been quite productive.
One of the problems with some BW shots is getting enough contrast in the right places to give it that dramatic effect. SEP presets and the freeform controls are great at getting deep contrast, but quite often the areas that are already dark end up
too dark after SEP processing.
I've found the following method I worked out very useful in getting around that.
Basically, I apply two SEP layers to my original, but the second one I do is also taken from the original, not the first SEP layer. I then put the high-contrast layer on top of the neutral layer, and brush through the darker area in those parts that are too dark to reveal a lighter section of the neutral layer below. If you don't have SEP you can still do this just by using different BW layers and adjusting the brightness/contrast of the layers.
Here's my original RAW.
I then apply a standard preset, such as 'neutral' to the colour shot. This needs to be fairly light because parts of it are going to be used to lighten some of the darker areas of the shot. You don't have to use 'neutral', you can just use the freeform controls on the right to brighten the base settings (you don't want to change the contrast if you do this as you want to keep the dark areas at a moderate level)
Here is the shot with my neutral preset applied.
I then go back to the base layer and run SEP again, this time applying a much stronger contrast layer. The choice really depends on what looks best for the shot. here is the shot with 'high structure' applied. For some reason this layer looks quite pale and not much different to the neutral layer in this screen shot, but it was actually a lot deep in contrast. You will have to take my word for it.
The SEP high contrast needs to be above the neutral layer when you have done them, so you may need to swap the layers around, depending on the order you did them in.
Then, add a layer mask to the high contrast layer, and select the brush tool (a soft one), set the opacity to about 30% (just hit the '3' key), and set standard foreground/background to black/white (hit the 'D' key). Then brush any
dark areas that are too dark and the lighter version of those dark areas which is below will come through.
Do any other touching up, sharpening and you are done. Some final dodging and burning may be needed to correct any bits you missed.
And this is my final image. It's probably difficult for you to see, but some of the darker areas of the monuments are now lighter and show more detail than they would have done had I just applied a 'high structure' preset on its own.