WHITE BALANCE PRESETS FOR ANY CAMERA

WHITE PAPER IS WHITE AND SHADOWS ARE GRAY, OR SO THE PART OF OUR BRAINS IN CHARGE OF NAMING THINGS WILL INSIST. BUT AS PHOTOGRAPHERS WE SEE BETTER. ON A CLEAR”DAY, WE OBSERVE THAT SHADOWED AREAS ARE BLUE BECAUSE THEY RECEIVE FILL LIGHT FROM THE BLUE DOME OF THE SKY. EVEN ON A CLOUDY DAY, BLUE PHOTONS FROM THE SKY ABOVE THE CLOUDS PREDOMINATE AS THE LIGHT SOURCE. VANILLA FROSTING ON A BIRTHDAY CAKE ILLUMINATED BY A DOZEN CANDLES APPEARS YELLOW, EVEN THOUGH WE KNOW IT S ALMOST WHITE. WHAT DOES YOUR CAMERA KNOW?

In the light-metering process, modern DSLRs can measure the dominant color of the incoming light and, when set to Automatic white balance, neutralize color casts from the light sources. White paper under candlelight becomes white again. Ita handy thing for straight documentary evidence shots, and Automatic white balance has its place, especially to preserve pleasing skin tones. But when color contributes to the mood of the image, we as photographers want to take control over the white balance settings.

We share strong cultural associations between color and mood, especially the contrast between blue (cold, harsh, dangerous, and isolated) and yellow (sunny, safe, hearth, family, and home). If youshooting summer wildflowers on a shady slope, youprobably want to use a white balance for shade because that setting reduces the color cast of the blue light source. But if youshooting bison in Yellowstone on a snowy winter day, where the frosty weather is part of the story, you might want to emphasize, not neutralize, the blues. A daylight setting will weight the colors with a bluer tone.

HITE BALANCE WORK?

The digital sensor in your camera captures incoming photons; the white balance setting adjusts the color values contributed by the red, green, and blue pixels in your sensor to the final image. This color calculation is permanently set when the file is saved in JPEG format. One reason many shooters prefer the RAW format is that the camera white balance settings are recorded and used in the image preview, but not committed until the RAW file is converted in the postprocessing step. If you forget to change your setting from Daylight to Tungsten when your wedding party moves from garden ceremony to indoor cake-cutting, you can adjust a RAW filewhite balance in Light-room later without any loss of image quality.

How does it work? Adobe Camera Raw (AGR) and Lightroom use two sliders to adjust the color captured by the red, green, and blue (RGB) pixels of the sensor. The first slider, Temperature or Temp, works on a continuum from blue to its RGB opposite, yellow. The slidernumbers are from the Kelvin degree scale of temperatures of various light sources (higher values are yellower). The second slider, Tint, controls a transition from green to its RGB opposite of magenta. The combined effect of these sliders is all you need to numerically describe the white balancehue (red and cyan can be computed from the two slider values).

So you can do as many photographers: shoot in the Auto white balance setting and plan to correct it in ACR or Lightroom. But herethe rub —the Temperature and Tint settings your camera would have recorded (presuming you remembered to change it in the heat of the bridal battle) are almost certainly different than the ones the ACR engine uses as its defaults (this is true in both Lightroom and Photoshop). The ACR values have one thing (and one thing only) going for them: they havenchanged since the beginning of time.

In the early days of ACR, someone at Adobe decided that daylight was 5500K with a tint of +10, and so it has been ever since. But that doesnmean your camera vendor used those values when calibrating your camerasensor and how its files should be interpreted. Take a look at the settings from a range of cameras:

Compare just the Daylight values for a moment. They areneven consistent within one vendorline-up. If you use the Nikon D700 with Adobedefault values for Daylight, youcome much closer to Nikonintended rendering for cloudy conditions. This is one aspect of postprocessing where one setting does not fit all.

Why the variability is a question for the sensor manufacturers. For photographers, forewarned is forearmed, and knowing that Nikon or Canondefinition of daylight does not equal Adobesettings can help us avoid an excessive amount of postprocessing twiddling with the Temp and Tint sliders in Lightroom. That is, if you do a little homework first to create a collection of presets that mimic your camerabuilt-in white balance settings to use instead of the Adobe pulldown defaults.

STEP ONE: Grab your camera, paper, and a pen; find a comfortable spot; and make a series of pictures in RAW format. The subject, focus, and exposure are irrelevant. You donneed to go to the trouble to match the light source in these images to the setting you use: the tungsten picture can be taken from the shade of your lawn chair. All we want is a RAW file captured at each possible white balance setting, except Custom or Pre (those settings are used when you measure the color of your light source in the field). Write down the name of the setting used for each image in turn because this information is, oddly enough, not reported in the Lightroom EXIF metadata, so you ll need to keep track of the order in which you shoot each test image.

STEP TWO: Choose File>lmport Photos and Video to import the images into your Lightroom catalog. Select Previous Import in the Catalog panel and click on the thumbnail of the first image in the series to select it. Press D to open the image in the Develop module. For this example, letassume the first Image you select is the one shot using the camerasetting for Daylight white balance (a Nikon D700 in this example).

STEP THREE: Open the Basic panel on the right side of the workspace. Note the As Shot settings for the Temp and Tint sliders. These are your cameradefault values for Daylight white balance. Write down the pair of numbers. Do so for every image in the sequence. Consulting your notes, correlate the slider values to the built-in white balance setting. Yousimply creating another column in the table on the previous page, using your own cameradata.

STEP FOUR: Now weuse the data from your notes to create a preset that mimics each white balance setting for your camera, but you have to trick Lightroom into making a preset for a custom white balance value. If you make a preset using the current As Shot values, instead of recording the numbers, Lightroom simply records a preset that reverts the image to its initial values.

For example, to make a preset for a Daylight white balance setting, select any other image in the series except Daylight. Click the As Shot drop-down menu and select Custom. Double-click in the Temp value to highlight it and type in the value from your notes. Repeat for the Tint value.

Make a preset by typing Shift-Command-N (PC: Shift-Ctrl-N), or click the Create New Preset icon (+) in the top right of the Presets panel header. Uncheck all the boxes except for White Balance and Process Version. Save the preset (see below for a suggestion on preset naming strategies).

STEP FIVE: Repeat this process for each white balance preset in the series. It doesnmatter which image you use to create the preset, so long as you change the values from As Shot to something else.

NAMING THE PRESETS

Ithelpful to name the presets such that theyforced to sort alpha-numerically as a group in the User Presets folder in the Presets panel. The scheme shown will even appear in the list by increasing Kelvin values. If you use more than one camera, youwant to repeat the test shots, make another group of presets specific to that camera, and name them accordingly. In this example, the presets are saved in their own folder. To create a folder, Right-click anywhere in the Presets panel and select New Folder. Give the new folder a name and click Create. Now you can drag the presets into the folder.

PRESETS TO THE RESCUE

The next time you need to adjust an imagewhite balance in Lightroom, begin by applying your user preset that best matches the lighting conditions in the image. For many situations, you may find that single preset is all the color adjustment youneed. If desired, you can use the white balance sliders to twiddle, err, or optimize the color rendition, but from a starting position that should eliminate gross changes in favor of minor tweaks. And, as with any of the Develop module settings, once you have perfected it for one image, you can sync that setting to other images shot under the same conditions, saving even more time.

CUSTOM WHITE BALANCE

In some situations, we want to match the white balance setting to the actual color temperature of the light source. Perhaps youshooting images for a clothing catalog or this yearline of products that must match the photos of the previous year. Attention to white balance is also essential in fine art portraiture. Ittime to break out the camera manual and learn how to set a custom white balance. The general process is to point your camera at a neutral target positioned under the desired lighting conditions for the mission-critical shots. Following the procedure for your camera, take a test shot. The camera uses this to calculate the white balance for the subsequent shots in the series. (Donforget to remove the target from the scene for the next shot.)

What s a neutral target? It depends on how critical your application, and how steep your budget. The X-Rite ColorChecker Passport target runs about $99. Kodak offers a collection of three 18% neutral gray cards for less than $20. Several manufacturers make lens-mounted accessories for measuring white balance that you screw on the front of the lens. You take the test shot by aiming toward the setup for your intended shots, then remove it to shoot. Or you can go low budget and grab a white coffee filter from your kitchen (one of those brown, environmentally sound recycled filters wondo here). Wrap it around the lens for the test shot. Will it be as precise as a more costly option? Probably not. But close enough for the price? You can decide that.

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