Preset White Balance on Nikon Digital SLR Cameras
I've written about white balance before, but a question that comes up frequently is just how one goes about using the preset white balance feature found on many current digital cameras. Although cameras come with any number of factory set choices, you can often do better by presetting your own custom white balance. I can't speak to all the variations in camera models that are out there, but as a Nikon shooter I'll try this week to dispel the confusion that often surrounds setting a custom white balance on Nikon cameras. The general process will be the same on other brands; only the buttons that get pressed will vary.
First, find something neutral hued that you can use as a target to measure white balance from. This could be a standard gray card or almost anything else that approximates the color of one (or rather its lack of color). It needs to be big enough to fill the frame with whatever lens you are using.
Although the topic at hand is called white balance, its best to avoid using a white target. The human eye is much better at judging color cast on a medium toned gray target than it is on something that is white. We tend to see any sufficiently bright object as being white, mentally compensating for any tint it may in fact have, while at the same time we relatively sensitive to that same tint if it is contaminating medium gray instead. Think about regular white office paper. Whatever you may have easy access to will seem perfectly fine for use in your printer or copy machine. But if you have two different brands on hand, put a sheet of each side by side and you will likely find that they aren't really the same color. The same phenomenon can be observed by looking at a wall painted white. It seems perfectly white until you look closely enough and compare it so something that actually is. The wall is likely a warm white and not actually pure white.
If you do feel compelled anyway to use a white target, be sure to expose it as medium since any color overexposed enough will record as burned out white, making any color cast measurements impossible.
As an alternative, people who use preset white balance often sometimes use a product called an ExpoDisc. This is an oversized filter with a gray diffusion substance inside. Rather than pointing your camera at it, you simply hold it over the front of your lens. ExpoDiscs aren't cheap, but the do work well if you have a need for one. It's also popular to use the white plastic snap on lids found on many re-sealable canned products (Pringles potato chip lids are a common choice). Others also use an ordinary white bleached coffee filter held over the front of their lens. To each his own.
Now that you have settled on your target, go to the Shooting menu on the LCD display on the back of the camera. Scroll up or down by using the multi-Selector until you get to the White Balance option. Press the "right" button on the multi-selector to display the sub-choices for White Balance. Scroll up or down within these choices to find "White Balance Preset" (labeled "WB Preset" or similar on some Nikon models). Press "right" again.
The next steps will vary somewhat based on which Nikon DSLR model you have.
If you have a newer Nikon camera, you can now select one of several white balance preset memories to record your setting to. My D2x gives me five possible slots labeled d-0 through d-5. So does the D200 I know. Having multiple memories allows you to save settings made under various lighting conditions you commonly shoot under. Pick the one you want to make use of and press the Enter key. If you really want, the D2x even lets you name these presets by pressing the center multi-selector button and choosing the "Edit Comment" option. Entering text via the direction pad is a bit tedious, but will certainly help with remembering what each is for. The D200 does not provide for naming white balance presets.
Older models such as my original D100 only had one white balance memory so this step gets skipped on it. Instead, some models want you to select the exposure mode you will use for setting white balance. You can use any exposure mode you want, but since you really want to end up with a medium toned image, my recommendation would be to use Aperture Priority (A). Press right one more time to return to the previous screen.
Now make sure your chosen white balance target is positioned under the light you will be shooting in and point your camera at it.
If you have a camera such as the D70 or D100 with a function dial, use it to select "WB." If you have a D2x or similar with a "WB" button on the back panel, press it instead. The word "PrE" will begin flashing on one of the LCD displays on the camera. Exactly where varies somewhat by model since not all models have the same number or placement of displays. If you have a small LCD below the main menu display on the camera back, it will likely be there. Otherwise check the top LCD panel near the shutter release.
Confirm that your exposure is properly set to record a medium toned shot and press the shutter release. If you've done everything correctly, you should see the word "Good" displayed on the top LCD and in the viewfinder. If not, you will be scolded with "no Gd" instead. Once you get the hang of using preset white balance, you probably won't have any problems, but don't be disappointed if your first few attempts fail. Just reread this or consult your camera manual and you'll soon figure out what you did.
You can now go ahead and shoot as normal. If you are shooting jpeg, your custom white balance will be used in camera. If you are shooting raw, the NEF files will be tagged with your custom white balance which will get applied when they are converted later on your computer.
Personally, I don't use preset white balance often since when shooting outdoors I want the golden colors of sunrise or sunset to influence my shots. When shooting indoors though, it can be a lifesaver.
Update 01/22/2007 - Reader DW wrote to let me know that the D200 does let you name your white balance presets just as the D2x does. Kudos to Nikon, and thanks to DW.