I was asked recently if an hdr image can be produced from a single frame. The answer is yes. That's what I did with the attached picture. Click on it to see it in a larger size.
Well it's not a true hdr image, but close enough. First there are a few things to know. Always shoot RAW frames to capture as much information as you can. Low and medium contrast subjects work the best. If you are shooting in a high contrast setting it's best to use the more traditional 3 image method.
I use Photomatx Pro to tone map my RAW files. It's fast and easy. There are times when I only use a portion of that frame. I do this by opening up both the original RAW file and the Tone Mapped file in Photoshop and use layers and layer maskes to combine the images.
In the image above I introduced one of my favoite filters to the body of the rower. The Lighting Effects filter (Filter > Render > Lighting Effects) can be used to light your subject in the digital darkroom.
There is another method I use, but for this you will need "Color Efex Pro 3.0 Complete". A Photoshop plug in worth it's weight in gold. A NIK Software product, it will work magic on your image. I learned this from Moose Peterson. Open Color Efex Pro 3.0 Complete and go to Tonal Contrast. Move the Highlight, Midtone and Shadow sliders all the way to the right. It will look over done. Move the sliders back to the left until you get the effect you want. You can always lower the Opacity slider if it's still too much. Quick and very simple. You may want to combine both of these methods or even combine it with the original RAW file. Experiment. I do it all the time.