A common problem when shooting in low-light situations is that even if you open your lens to its lowest f-stop number, you're left with an image that's far too dark. One obvious remedy is to add more light. But what if you don't have more lights available to you? That's where the gain increase switch comes in. This free video cinematographer's guide will show you how to use digital gain settings to amplify available light to get better shots in less-than-ideal environments.