Because the ubiquitous white background portrait is so commonplace, many people think it’s easy to achieve. Simply put your subject in front of the camera against a white background, preferably with a flash or strobe, and take the picture.
Unfortunately it’s not as simple as that. Doing just that would result in a photo with either a gray, dull, muddy toned background. The best possible result would be an off-white background after you have done some edits. That’s not the only issue though, you’d be dismayed to see unwanted shadows everywhere too.
I have replicated the setup with my little model Sven – Kristoff’s beloved reindeer in the movie Frozen. It is easier doing this on small scale subject as the lights are oversized in comparison. With people, to do this to scale, you need to have massive size octoboxes and flags. But this tutorial will show you the process clearly.
Here are 3 rookie mistakes to avoid when trying to achieve a 100% pure white background:
Mistake #1 The background is not lit properly
The background must be lit with approximately two stops more light, than the amount of falling on the subject. For example, if you want to photograph your subject at f/8, set your background lights to two stops brighter, so the meter would read f/16 on the background.
Note: You need to meter both background lights separately, so that when metering for the main light (on the subject) you would turn the background lights off, and vice versa. When both the background and main lights are on, your meter should still give you f/8 on the subject, because you are metering the light that falls on your subject and not on the background.
The photo below (right) shows what it looks like when you don’t light the background at all. You get a tone and color other than the intended white. In the photo on the left the background was lit, but there was no main light illuminating the subject; thus the resulting image is almost a silhouette of the subject.
My camera settings for all the shots in this setup were: ISO 250, 1/160th of a second, shot at f/8 for Sven, (the background read f/16). The speedlights were set to 1/16th power. I rarely use them at full power because the batteries run out very quickly that way. If you are using the SB900 Nikon, firing at 1/1 power, not only does it drain the batteries very quickly, but also makes the flash overheat. Nikon has solved this problem with the SB910. These are some reasons why I did not shoot this at ISO 100. The camera used was a Nikon D750, which handles noise superbly, so that ISO is not an issue. Two SB910s and one SB900 were used for this setup.
The photo below shows a pull back of the setup with only the left background light firing.
You will notice in the two images below that only the right background light fired on the left photo, and only the left background light fired on the right photo. This lighting is acceptable of course if that were your intention. The main light was positioned at a 45 degree angle on camera right. I wanted to bounce my flash onto the white rogue bender to modify it.
You may also notice that on the left photo (above) there is a pleasing shadow of Sven behind him on the background – because the left background light didn’t fire. Where the background light did fire on the left, this shadow was eliminated (right photo above).
Below is the setup with all three lights firing correctly.
Now that you have your background and main lights set up, you need to make sure these lights only hit the intended subject. This leads us to the next rookie mistake… separation.
Mistake #2 Not enough subject background separation
Because the background lights are so much brighter, you need to separate them from the main subject. There are two key ways of doing this:
You can use anything block to flag your lights; the black side of a reflector, black cardboard sheets, black foam core. Black does not let light in, instead it absorbs light rather than bounces it. It also blocks light from seeping through to places where you do not want it. If you don’t flag (block) your background lights, your subject will get a halo effect and look very backlit.
Once you have flagged your lights, you need to distance your subject far enough away the background (and background light) so that any spills won’t touch your subject. This depends on your personal preference and intention of course – you may want some spill on your subject for a certain look or effect, or you may not.
If you do want some spill on your subject, make sure to run a few tests with various lenses, as chromatic aberration tends to occur around the edges due to the abundance of light. Some lenses are prone to chromatic aberration irrespective of aperture, while others can handle it very well even at wide apertures, where it is most commonly observed. Also, be careful with the amount of spill you allow so as not to chop off parts of your subject from the spill overexposure.
The photos above show a properly lit Sven. The two background lights firing at f/16 and the main light firing at f/8. There are no unwanted shadows on the background, as was my intention. However, I wanted to have a reflection and shadow in the foreground. This leads nicely to the third rookie mistake to avoid…a floating subject.
Mistake #3 The subject is floating
If you do not include some floor shadows, your subjects will look like they are floating on white air, or cut out and pasted on a white sheet of paper.
The best tip for avoiding floating subjects is to use a reflective surface like translucent white plexiglass, or white tile sheet, as a base for your subject to stand on. You can adjust the opacity of this reflection in Photoshop during post-processing, but having the reflection shows that your subject is planted firmly on solid ground.
The left image shows Sven floating, and on the right you see the reflection showing Sven standing on solid ground. The latter looks more pleasing and natural, and not like a cut-and-paste job.
Bonus Mistake #4 Overexposed background
Be careful not to add too much light to the background. If you go past pure white and really overexpose it, the white will start almost glowing around the subject just like if you had sun flare outdoors. It lowers contrast and your subject looks like that have a bit of a halo, as you can see in the images below.
For more tips on a white or high key background see: 4 Tips for a Perfect White Background in High Key Photography
I hope this little tutorial has shed some light on basic techniques for shooting a white background, where you want the background to be 100% white, and that it has dispelled any mystery over how to achieve this look. If you have other more advanced techniques, do share them here!
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