You'll be taking several shots at different exposure levels. On a Canon Digital Rebel, you change the exposure level by holding the Av button on the back and then moving the scroll wheel which is behind the shutter button. In our case, we moved the exposure to -2 and took a shot, then up one notch to take another shot. We continued until taking shots up to and including the +2 exposure setting. If you don't want to take so many shots, you can just do -2, -1, 0, +1 and +2. You can also use the bracketing feature in your camera to take different exposure shots automatically one after the other.