I often hear questions about how to shoot with a white background. The first time someone tries it, they will typically get a nice white spot somewhere, and a gradual fade to gray as you move away from the spot. Then, they spend a bunch of time in Photoshop making it pure white as they originally intended.
I typically spend extra time trying to get things right in the camera, so I don’t have to fix them later in Photoshop. There are a number of reasons for this, but the bottom line is I want to reduce the total time per-image I have to spend in post processing. I sit in front of a computer screen just plenty, thank you, so if I can do something in the studio to reduce it, count me in!
So let me try to talk a bit about one way to get a nice, all-white background, without Photoshop.
If you only need to shoot head and shoulders, or perhaps even down to the waist, you might be able to get away with a single light on the background. Maybe not, but it’s at least possible. But I’m going to assume you have two lights for the background, and go from there.
This is easier than full length, because there’s a limited amount of backdrop visible behind the model. So really, you only need to light that part evenly.
I typically use two medium-sized softboxes, one to each side of the background paper, each pointing about 1/3 of the way in from the edge. Meter them together, so the whole area behind the model meters within +/- 0.2 stops or so. And overall, you’re looking for about +1 stop brighter than you’re going to use for your key light. More than that, you’ll most likely run into a lot of spill and flare problems; less than that, you’ll have problems getting your background to look pure white.
And you don’t have to use softboxes on the background here – just pick something that allows you to get even coverage across the part of the background that shows behind the model.
I start with the same two medium softboxes pointing towards the white seamless background; if you have more lights, 4 heads is even better. I start with the boxes about 5 feet high, pointing in about 1/3 of the way on the background. Then start metering again all across the background – top to bottom, left to right, and keep adjusting things until you get it pretty even (as before, ideally you want this +/- 0.2 stops).
Now, you have the problem of the floor the model is standing on. This is a tough spot to light. What I typically do is place a large sheet of plexiglass material (white or clear works) on top of the white paper you’ve pulled out. This plastic sheet will actually reflect the light hitting the background, and once you get things adjusted right, will seamlessly blend into the background.
The tough spot with all of that is the back edge of the plexiglass; you’ll sometimes get a shadow there, which appears as a dark line going across the picture. You can adjust the background lights a bit to compensate for this – try pointing them down a bit more. Or…you can use a platform.
I usually use a platform that’s about 10 inches high. I cover the platform with white seamless paper, and then put the plexiglass on top of it. The model stands on top of all of this. Once you do this, you effectively hide the part of the background that is most difficult to light (the part on the floor), and the plexiglass foreground reflects the background light…with no seam.
Note in the lighting diagram above I’m not showing the fill – just a main light and two background lights, with the platform. (Many thanks to Kevin Kertz for the lighting diagram template!)