There has been a lot written (and put onto video) over the years advocating the use of a single flash and there’s nothing wrong with that. They’re often packed with wonderful advice that’s geared towards either educating those who’ve never used flash before or helping those with far too much gear to really limit themselves in order to master that most basic of techniques.
But once you’ve mastered lighting up your subject with a single flash, how do you go about adding another? Why would you even need to do so? Well, in this video, Gavin Hoey walks us through the potential problems of only using a single light that can only be overcome by adding another and offers up three different ways we can add a second flash to our setup in the studio.
As with most of the advice on just using a single light, these two-light setups walk us through the basic principles and reasons why you’d want to add a second light to your setup. The first is as a hair light (also often called a rim light, especially if it’s not just lighting the hair), which provides some separation of our subject from the background. The second technique separates the subject from the background in a different way by using the light to illuminate the background itself rather than our subject.
The third technique is to use the second flash as a fill light. Gavin gets a little more creative with this and adds a gel over the fill light. This can be a great way to add some in-camera effects to your shot to totally change the feel and mood of the images without having to spend ages in Photoshop trying to change colours of just parts of your image after the fact in post – although you could do that, too, if you didn’t have gels to hand. Of course, you don’t have to use a gel with a fill light and it’s pretty common not to, but it can create some nice colour contrast in your image.
There’s no hard and fast limit to the number of flashes you need for any given photo. I’ve got about fifteen of them. Joe McNally’s used 47 in a single photo before now. It’s all subjective and based on your own vision of what you want to create. The trick is to understand the light, how it works, where you need it and when you need to use one, two, three or forty-seven of them in order to let the camera’s sensor see your vision, too.