Lightroom Split Toning, Not your Average Black and White
Lightroom has a (little used, at least by me!) Split Toning panel in the Develop Module. It is quite powerful and can create very dramatic images. What its not is a fix for a bad photograph or a crutch. Used sparingly the a photograph split toned can be a nice addition to your portfolio, website or gallery of images.
There are a few presets for split toning that come with Adobe Lightroom 3. I am not a huge fan of presets because I believe every image has its own character and style that should not conform to what someone else thinks it should. That doesn’t mean the presets can’t be used as an educational tool to help you to learn and expand your knowledge of photographic processes. In my opinion a split toned image starts out at capture as an abstract, then is tweaked, pushed, pulled and manipulated to add to its abstract nature with two tones. One tone for highlights and the other for shadows.
When using the tool I suggest increasing the saturation quite high and then decreasing it to taste, allowing you to see the adjustments much more easily. Since, IMO, an image is abstract when using this tool don’t be afraid to use the other options available to you in Lightroom. Applying a wacky white balance, exposure, contrast, vibrance, saturation, etc etc can only increase the interest in the image and give the viewer a sense of the image you had in mind when clicking your shutter.