One of my favourite ways to use a light is a hair light. Add it to almost any picture to add some interest, contract, and separation from the background.
So you go from this picture of a very nice student in one of my classes recently:
Lacking a hair light
…to this subsequent picture of the same young lady:
Using a hair light
Much nicer, no? And look, even the smile improves!
OK, I am kidding about t he smile. But the picture is better. A dark-haired person against a dark background particularly needs a hair light.
It is aimed directly at the subject from the back, usually diagonally. Use a grid (like the Honl Speed Grid) or a snoot for even more controlled light (like the Honl Speed Snoot).
Hello Michael
I see the different with the hair lighting. Now you have separation with the model and the background,this shows depth in your photo. I have to ask is the model left side overexposed now because of the hair light. I prefer my exposure ½ stop underexposed rather then overexposed. As a photographer is this a correct way to think.
Indeed, your thinking is right: she’s a bit hot there, yes. That is why you meter (or measure, or at least set) each light separately. Be careful with TTL, as flash adjustment (down) will be necessary. But also be careful to not underexpose: the hair light should probably be a stop darker than it is here (an easy adjustment in post – but best to get it right in camera!)