This is the basic color balance that begins the balance/neutral process. Place Tone Balls™ or a Macbeth Colorchecker™ in the scene. Verify that you’ve selected at least a value of 5 for the Sample Size in Setup>Preferences. Start with the Meter function and adjust the lighting and aperture for the scene you’re interested in shooting. On a theoretical level, you may want to adjust transition-of-tone before you balance each image, however, it’s not required. After the shot is basically lit, pull down under Setup and click on Balance. A dialog box will appear, informing you of the advisability of making a Dark Capture image if the dark value (directly related to ambient temperature) has changed markedly since the last time you made a Dark Capture. (If the dark value has changed, capture a new Dark field; Setup>Dark Correct>Capture). Click OK and another dialog box will display the current dark value. Compare this value to the last known value that you should either write down and affix to the monitor or, remember (in air conditioned environments the dark value will not appreciably change). After you click OK, the camera will shoot three times and a greenish image will appear, displaying a prompt to close the dialog box and click on a known neutral white reference reflectance in the image. This assumes you’ve placed Tone Balls™ or a Macbeth Colorchecker™ in the scene prior to the Setup>Balance procedure. Move the cursor across the neutral reflectance in the scene, reading the Green channel; you’re looking for any value between 10 and 30 if you’re using the 0-100 scale and Zone VII to IX if you’re using the 0-10 Zone System values. If you prefer, you may zoom and scroll around the image before clicking on the neutral reflectance. You will find Tone Balls™ to be particularly convenient for choosing a reflectance within the desired range. The spherical nature of the Tone Balls™ allows a transitioning selection of value from highlight to shadow; move the cursor along the transition until you get to density numbers that are acceptable. Click on the acceptable reflectance and another dialog box will display (in the following order) the values you selected: R,G,B, and the current Dark value. If the Green value is within the acceptable range, click OK. If it is not, you may re-select the neutral value by first selecting NO. Try this feature of the balance procedure: Select NO and make another Balance selection.
Once you’ve chosen an acceptable value, click OK. Verify the accuracy of the balance procedure by shooting another capture of the scene containing the Tone Balls™ or Macbeth Colorchecker™ . Neutral reflectances should render neutral. Verify neutrality by making sure any neutral reflectance reads R-G-B values whose difference does not exceed 2 values when read in 0-100 or .2 when read in 0-10. Make sure you read values from highlights, mid-tones, low values, and blacks. All should meet the 2 or less test for neutrality. If they do not, the Setup>Balance is not valid. Do not assume the computer made a mistake if the values are not reading neutral. First go back as close as possible to the spot where you first chose to balance. That area should be neutral. If other areas are not neutral, look to see if the change away from neutrality is a result of a light source that is causing the shift away from neutrality. If the shift is caused by a dissimilarly colored source, consider filtering the offending light source. A color temperature meter is invaluable for quickly filtering sources to the 200 degrees Kelvin or less tolerance we’re looking for. You can, however, use Tone Balls™ to validate the color filtering of light sources. If you cannot make neutral shadows in this manner check out the redout instructions in the Neutralizing and RedOut Curves topic.
This PhotoShoot feature allows the shooter to click on up to 20 different neutral reflectances in a scene providing a more accurate “white” balance because you can choose neutral reflectances of various brightness, choose some whites, various grays, and some blacks. This form of
balance requires at least three samples to perform its routine, place plenty, there is no penalty for selecting more than three sample sites.
Placing more clicks in a specific area will give more emphasis to that area when calculating a balance. If you use this feature, try to place clicks as evenly as possible along the transition from highlight to shadow. Note that RGB values display the actual values on the left, and what they will become after you Apply the routine on the right.
Neutral Program has an ability to map selected points to preset values. While we do not recommend this model for making transition of tone, you can for example, make the patches on a Kodak Q-14 map to specific values. Click on a selection in the list, highlighting it, in this case, line 19. The values 68-66-67 have been remapped to 70 by clicking the insertion point above the arrow. Enter the value you want, in this case 70. When you Apply, that patch will be neutralized and moved to 70 percent.
Why do we use 2 or less as our model for known neutrality? In the 1930’s a French group decided to try to describe color. Key in the description is who decides what color is, and perhaps more importantly, what is good color? They founded a group called CIE or Commission Internationale de l’Eclairage (translation: International Commission on Illumination). They shrewdly (and accurately) decided the description of color should be decided by humanity rather than a few experts. The target audience is you and me. The devised some interesting tests, one of them was for neutrality. Imaging someone gives you a gray chip and asks you if it's’ neutral. Could you tell if it is warm, cool, does it have a surplus of red, green, or blue? The chips used were carefully controlled for color content. Some people were very good at deciding neutrality. Of course experts, used to looking at color, were best. Not even an expert, when handed a chip whose neutrality was within 2 units of RGB deviation when expressed in a 0-100 scale could say neutral or not neutral with any certainty. That’s why we use 2 or less for our neutrality, not even an expert can say, “That’s not neutral.”
How do you get wonderful balances? It can be more involved than simply running our balance routine. You might have to look at the light sources if you’re using more than one source or if you’re using a fill card to trim contrast. Why? Because any secondary source (even if it’s a reflector) can have a dissimilar color temperature to the primary source. Additional source beyond two can also have differing temperatures. How do you know the respective temperatures of multiple sources? A color temperature meter will work. What if you don’t have a color temperature meter? You can use Tone Balls™. Shoot the Tone Balls™ with two sources, one on each side of the balls. Balance on one of the sides. Shoot the balls again and if the two sides are the same color, those heads match within 200 degrees Kelvin. If they do not match, filter the head until they do match. It would not be an excessive approach to monitor the temperature of all your sources, reflectors included.
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