Typically, the first light-shaping tool a learning photographer reaches for is the umbrella. The next logical step is a softbox because it typically offers more directional light and, as a result, more control. While soft boxes are useful and effective in their normal configurations, you can also tweak them to get some more interesting effects. In this video, Andrea Belluso explains some of the options you can implement when using soft boxes.
The video is produced by Profoto and therefore it’s filled with pitches to buy their gear, but the actual info is applicable across a breadth of soft boxes from the fancy high-end stuff like this to the basic and even DIY stuff some of us work with.