Understanding exposure - exposure triangle) and how it controls timing and depth of field. Now were going to completely confuse you and throw in a fourth element; flash.
In a previous post we learned how to use fill light in high contrast scenes. When using flash for fill we are simply taking our existing exposure and adding light to the dark areas. The nice thing about using flash is that we can control the way the camera captures ambient light just by using the power of the flash unit to compensate our exposure.
One simple technique to illustrate this is the "invisible black background" technique as illustrated in the photo at right. The results are very dramatic. and the interesting thing is that this was all done in broad daylight out in the open.