Photography White Balance Techniques
Color The Background
Often we take photographs outside, pointing our cameras into the deep-blue sky. The shutter clicks, then we check our LCD screens and find that the sky looks unsaturated in color—clear and colorless, more gray than blue—and even placing a polarizer filter on our lenses doesn’t always seem to help.
By applying modified film techniques to our digital captures, we can color the sky as we wish, right in the camera, without relying on glass filters and various film types (emulsions).
In this photo of American Idol star, Amy Davis, I used a Rosco green gel over my flash with a custom white balance to create the magenta sky in the camera.
In the days of film, professional photographers simply used an 80A (blue) filter over their lenses when they were using daylight-balanced film and working with tungsten lights. The warm light created by the tungsten light source would fall on the subject, and the blue 80A filter would cancel out the warmth. This balancing of colors worked great for the illuminated subject, but any background or foreground not illuminated by the tungsten light source would become blue. This made for a great, saturated, blue sky or background. However, it also meant that you had to compose the image with a dense filter on the lens, making the objects in front of the lens harder to see and focus more difficult to achieve. With digital, we can simply set our white balance to 3200K, or tungsten. On some cameras, you can also set the incandescent light white balance setting.
Playboy Playmate Holley Dorrough was photographed with a light modified by a 3/4 CTO gel to help create the deep blue sky.
When working digitally, we do not need to contend with the depressed, “blue Monday” feel when we look through the viewfinder, as there is no filter to cut the amount of light entering the lens. We also eliminate the need to purchase a high-quality, multicoated filter. (A lens is only as good as the last piece of glass on the front of it.)
While this sky saturating technique is proven and produces great results, not everyone likes to carry hot lights on location. Not only are tungsten light kits bulky, but they require at least 1000 watts of power. Also, the light emitted is physically hot and can melt the subject’s makeup away. Because they are bright, they can make the model squint. Finally, a tungsten bulb is a very specular light source, and the hard light it produces is never flattering to a model’s complexion.
Like most photographers, I don’t want to carry more photographic equipment than I have to when I am shooting on location. The solution is simple—I can place a Rosco ¾ CTO (continuous temperature orange) gel over the studio flash or camera flash itself. I would recommend a portable studio flash unit with a 22-inch beauty dish or a medium softbox attached as the final light modifier.
CTOs are commonly used by Hollywood photographers and cinema photographers to create warmth, especially when applying edge, rim, or accent lighting while creating dramatically lit photographs. Rosco CTOs come in various fractional strengths, from 1/8 to a whole (also called a “full”) CTO. My personal favorites for edge, hair, accent, and rim lighting are the Rosco 1/8 and 1/4 CTOs, but to get the sky a nice, deep blue, it should be at least a Rosco ¾ CTO, or Rosco #3411. This gel costs around $6.00 for a standard full sheet and also comes in more expensive rolls. You can order them from Samys.com online or purchase them at your local photo store or theatrical supply house. The Rosco 3/4 CTO is designed to convert the color temperature of any 5500K light source into a 3200K (tungsten) color temperature light source.
Here you see a Chimera, Super Pro Plus softbox with a 3/4 CTO, removable velcro panel. This panel will convert studio flash, a 5000 Kelvin light source, into a 3200K light source that mimics tungsten color temperature while still maintaining the softer qualities of a softbox.
I often tape the gel over the flashtube, then attach my Chimera softboxes or tape the full gel sheet over my Hensel beauty dish—it fits perfectly. Chimera makes a ¾ CTO diffusion panel that replaces the standard white diffusion panel on a softbox. Sometimes I prefer using the CTO panel to placing a gel over the flashtube, as it allows me turn on the modeling lamp on the flash head without the heat of the tungsten modeling bulb melting the gel.
These Rosco CTO gels and panels instantly provide the color of tungsten light without the heat and harshness! As a last resort, though not as flattering to the model’s skin, I can cut a piece of the Rosco CTO gel from a sheet or pull out the sample from the free sample gel books most photographic stores provide to their customers and tape it to the front of a pop-up flash or on-camera flash.
When I have changed the color temperature of my flash to tungsten and have set my white balance to match, whatever area the flash doesn’t illuminate will turn some shade of blue, depending on the amount of ambient light. For example, if I place a model outside under open shade, then place a Rosco 3/4 CTO on my flash and set my white balance to 3200K and depress the shutter button, the flash will fire and illuminate my subject. My subject will look as she should when illuminated by a tungsten source, but the background and sometimes the foreground will turn blue if it’s illuminated with daylight or a daylight-balanced light source.
Because I prefer to shoot warmer tones when photographing models, I often “bump up” the warmth by setting my camera between 3700 and 4000K (the amount of the adjustment depends on each model’s skin tone) instead of the normal 3200K. With this technique, my camera doesn’t know if I’m using flash or a flash covered with a Rosco CTO, it only knows what I tell it from the settings I set. In this case, I’m using the 3700–4000K setting to trick the camera into thinking the light source is slightly cooler than tungsten. Therefore, the camera will add more warmth than would be the case if the white balance was set to 3200K.
In this photo of American Idol star Amy Davis, I simply changed the gel from Rosco green to cyan, from the previous photograph, to make the sky turn red, in the camera using a custom white balance.
Now let’s pretend I want to make the sky red, not blue. I simply tape a Rosco cyan (opposite of red) gel over my flash, then have my subject hold a white 100 IRE card (some camera manufacturers prefer an 18 percent gray card) while I photograph the card with the cyan-gelled flash. (Note: If you don’t have a 100 IRE white card available, a white t-shirt or white towel will work.) The key here is to fill the entire frame with the white card or white object, store the image in the camera, and select it as your white balance image—a custom white balance. Most cameras have their own proprietary method for setting a custom white balance, so please refer to your camera manual.
When I photograph my subject with cyan-gelled flash and use the custom white balance I’ve just set, the subject is illuminated with cyan light, but the camera adds red to ensure a known white will remain white with that light source. In this case, then, the background will turn red and the subject will be rendered with a normal skin tone.
While a 100 IRE white card is best for setting a custom white balance, white towels work too. Here you can see where I was custom white balancing to a green gel placed over my portable studio flash.
Please keep in mind, the custom white balance method over the manual white balance method is not always an exact science. With the Rosco ¾ CTO over a flash unit, you can easily select the exact number (3200–4000K) as the Rosco ¾ CTO is an exact science when used in conjunction with on-camera or studio flash (5000–6000K). Unfortunately today, with the more complex gels (cyan, magenta, red, etc.), you must do a custom, not manual, white balance, and while most cameras can handle this well, some only come close. When using these colored gels, it’s best to capture your images in the RAW (or the highest quality JPG) mode. In the RAW mode, using the camera’s conversion software or image-editing software like Adobe Lightroom, you can tweak the white balance for better accuracy in establishing a natural skin tone on your subject.
This technique of using gels with flash units was used in the old film days too—however, I’d have to shoot through an exact opposite gel or filter and I was limited to using colors with exact opposites. With digital, we have a larger range of color options because we’re using custom white balance through the camera’s proprietary software, thus it’s more accurate without shooting through a plastic gel or colored filter. One of my favorite effects is placing a green gel in front of the flash so that the sky becomes magenta. All this is done in the camera, not in postproduction.
Some photographers will claim that when shooting in the RAW mode you can white balance during the RAW conversion and avoid having to do a custom white balance during the shoot. I don’t recommend this, as you’ll get a more accurate and correct skin tone with the correct white balance setting during the shoot, especially when working with strange colors and not the standard red, green, blue, and their exact opposites, cyan, magenta, and yellow. I might add, if you don’t do the custom white balance when using colored gels on your flash, your subject will look extremely off-color in the LCD screen, and when your subject wants to view the images during the shoot, they will think you’ve made a serious lighting mistake. Always do all you can in the camera during the shoot and you’ll love yourself for it during postproduction—it saves heartache, heartburn, and time by shaving hours off postproduction.
While these techniques are great for outdoors, don’t limit yourself: you can apply this technique indoors too. As an example, if I photograph a model in the studio on a white seamless or a white cyclorama (cyc) wall with the main light covered with a Rosco ¾ CTO, I’ll simply set the white balance on my camera to 3200K or slightly higher, then aim two regular flash units without CTO or gels into the background. Now my background should take on a more blue appearance as it is reflecting “daylight-balanced” flash back into the camera (5500K) and my camera is set to a more tungsten white balance (3200–4000K). You can do this also with other colored gels using the custom white balance technique previously explained for cyan or green gels to create red or magenta backgrounds.
When working at a residence or building with windows that allow daylight to filter in, I’ll get the same blue-tinted effect on any light coming through any windows or glass block provided I use a Rosco 3/4 CTO gel on my main light while white balancing to tungsten. Hollywood photographers often use this technique to create “blue moonlight” or a nighttime effect during the daytime.
I can do just the opposite by white balancing to daylight and using tungsten light sources as accent, rim, hair, or edge lighting and using regular flash without any gels as my main light. As an example, my studio lights have tungsten “modeling” lamps (the light that is always on when your studio or portable studio strobes are turned on). By simply placing a 7-inch reflector on my monolight with a 20- or 30-degree grid behind my subject and aiming it at their back or hair, I’ll get a beautiful golden glow created from the white balance mismatch of daylight and tungsten.
Nikki was illuminated with a 22-inch beauty dish, fitted with a Rosco 3/4 CTO gel to convert the studio flash from 5400K to 3200K color temperature. The glass blocks are illuminated from behind by natural sunlight, thus their blue color as the camera white-balance is set to 3700K.
The key here is to drag my shutter so the camera will pick up the less intense tungsten light from the modeling bulb. I’ll make sure to turn off the flashtube on my studio monolights in order to do this. I won’t worry if my shutter speed is 1/30 or 1/10 second, as the real shutter speed for my subject is duration of the flash (or my main light), so my subject will be tack-sharp when the shutter button is depressed. Most great flash units like the Hensel, Dynalite, Profoto, or Broncolor have short flash durations, thus it gives me a great shutter speed to capture my subject.
One of my favorite places to utilize this technique is when photographing a model while in a master bath area of their home. Most of these rooms have glass block windows that allow ambient light to filter in, and by placing a Rosco ¾ CTO on the Hensel beauty dish that will illuminate my subject and setting my camera’s white balance to 3200 to 4000K, all ambient light from the glass blocks will turn blue. I often get some “spill” ambient light that will add a tint of blue in the white tub, foaming bubbles, and the water that contrasts with the warmer tones of the model’s skin. The end result is an image with great contrasting colors, not just plain flash or white.