I just drag the single raw file into Photomatix cause I'm lazy lol so it is a fake HRD as I call it. If you shoot several frames you can do an actual HDR with Photomatix, PS, your camera (if equipped) or use another HRD problem to enhance the image.
It enhances the image and brings out contrast, etc. Hard to see but the circled area is called painterly. You can enhance more but I find it can over cook it, even for B&W. There are all types if fine tuning settings on the left.
Final image. Becomes a TIFF after I save it and I drag it into PS and open the B&W converter. I discovered this by mistake one day trying to figure out how to get a richer look for my B+W shots.
I don't use it for every shot as it does not always come out and I usually have trouble repeating an image. I'd need to record all the adjustments and there are quite a few, especially in the B&W part.
Here is one of my favourites. Gave the wet rocks a sheen and the contrast in the trees came out nice. You have to sharpen quite a bit too. The beauty is it is like a box of chocolates. I never know what I'm going to get.