On the Expo floor, photographer Jim Schmelzer will give you a better view on the craft with Understanding Portrait Lighting. You can go in-depth with him during his pre-conference photography workshop on The Quality of Light In Depth where he will give you a step-by-step explanation of lighting theory, studio lighting, and how to control light. There is also a more brief version of this workshop during the regularly scheduled conference called Quality of Light that covers topics such as white balance and inverse square law.
This is just a small sample that awaits you at Photoshop World. You will find an entire track devoted to photography lighting techniques in the Photoshop World schedule