One of the parameters that determine the quality of a picture is white balance. A good adjustment lead to pictures that conserve the nice and bright colors the original scene had, while a bad adjustment usually tints all colors with an orange or blue mist. This mist not only distorts all the colors but also gives the sensation of a really poor quality picture. This adjustment is especially important in the fields of photography that requite a great purity in color, e.g., when photographing a painting or in scientific photography. The correct adjustment of the white balance is very important when saving the file in JPEG format, as it will be difficult to modify it afterwards. Besides, that doesn’t mean that when shooting in RAW format we can avoid adjusting it. A good white balance will allow us to measure light in a more effective way and to predict better which exposure values are the best for our composition, without the risk of “burning” any of the color channels by mistake.
White balance arises from the fact that white light we see is not usually pure white. Some light, like the one produced by candles or incandescent bulbs, have a dominant in the red color. The scattered light by the clouds in a cloudy day tends to be tinted with blue, and fluorescent light usually has an excess of light in the green part of the visible spectrum. This dominant color tints the object we are photographing, more noticeably the whiter ones, as they are the ones which reflect a higher amount of light (i.e. if you are absorbing all incident light it doesn’t matter which color was originally, as the object is returning none to the camera). The brain is very good in correcting this tint, so you can always identify a white object as white regardless the light used to illuminate it. But the sensor doesn’t correct anything, it just collect photons of different colors and count them to produce an intensity level for each of the primary colors. The white balance adjusts the offset of the three channels to the point that a known neutral color appears without any predominant component.
In the film era, you had to know in advance what kind of light you were going to use, and load the corresponding film. The worst part is that there only existed a couple of temperature colors: tungsten for warmer lights and daylight for neutral. With the appearance of the digital world, cameras allowed more adjustments, as it was an easy operation to implement on the camera. Still, in many cameras, you still had to adjust in advance the values because the picture was saved in JPEG. Even nowadays, using RAW format, a good adjustment on the spot is desirable. It happens that when you decide to adjust the color temperature for a picture a few days after taking it, it is very difficult to remember the true color the scene was at that moment. The only solution for getting reliable colors is to adjust it before taking the picture and getting sure that the value is correct before leaving the place.
Live view supposes a great advance for adjusting this parameter. Instead of having to guess the correct value, you can simply point your camera to the subject, adjust the values and see how each value modifies the overall aspect of the picture in the screen. The target is to stick to the value that provides an image in the screen as similar as possible to the scene that you are just watching with your eyes. This way, the scene will be saved with its true color and, afterwards, you can modify it if artistically needed without losing the original correct value. In low-end cameras a fine adjustment is not possible, and usually you have to stay with the closest profile the camera allows. On higher-end cameras, usually a color temperature dial is available, where you can select an exact value. The use of this mode is preferred to the predetermined ones, as it offers more control and the possibility of choosing values between the predefined.
So, the next time you visit a museum, a church or an art gallery and you want to take a picture, try this method to get the correct value. You will notice how simple and fast is, and how great the results are.
This morning, when Mr. Leprechaunius Smith and Mr. Brainsqueezer woke up, they found a new visitor near their house: Ms. Little Salmon. Amazed by such discovery they hired their favorite photographer to take a picture of the event.
The mixed lightning makes taking the picture complicated. From the left side the scene is illuminated by the sun, with a warm yellowish light. From the right side the still-deep-bluish-sky provides a cold blue fill light. The composite illumination produces a complex mix that the photographer wants to capture.
If the photographer uses the Shadow white balance the effect of the blue fill is neutralized, increasing the effect of the warm sunlight. This is not the desired effect. Although the sun is an important factor on the picture, here it monopolizes the light destroying the desired mix of lights characteristic of the moment.
On the other side, if the photographer uses the Tungsten white balance the effect of the sunlight is neutralized, covering the entire scene with the blue diffuse light. Sunlight is transformed into a neutral “white” light that lacks of the expressive power desired.
Using the Live View, the photographer can adjust the temperature parameter of the white balance to the exact point where both lights are seen exactly as in the scene that is in front on him. There is enough blue fill light from the sky at the same time that the sun keeps enough warmness to imbue character to the picture.
Now all three of them will have a nice memento of their first meeting!
Do you have another trick to adjust white balance? If so, share it in the comments section so we can all learn something useful.