White Balance, The Colour Of Light

Our eyes automatically adjust to different lighting conditions as we move from place to place, and we don’t tend to notice the subtle colour tints it carries. Nevertheless, these variations are much more obvious to the camera than to use and you may need to change your white balance settings to correct for them.

For example, the light from a candle has a warm red/orange colour cast, whereas an energy saving light-bulb emits light with a cool blue/green tinge. Midday sunlight is a clear white whereas shade has a blue tint. The aim of changing the white balance is to make whites appear as they would under the tint-free light of the midday sun, and keep the skintones accurate.

Often, the camera’s automatic white balance (WB) setting will do a fine job of measuring the ‘temperature’ of the light and adjusting accordingly. If, however, your images appear off-colour, you may want to manually select a white balance mode appropriate to your lighting situation. This is as simple as holding down the WB button and rotating the dial through the choices – tungsten, florescent, daylight, cloudy, shade, flash etc. For a more accurate reading, use your camera’s custom WB function and position a piece of white card in front of the camera, under the lighting conditions you want the reading for. Fill the viewfinder with the white card and take the shot. The camera will calculate the correct colour settings so that the white card appears correctly and will use those settings until you take another custom WB reading or change the WB mode. Alternatively, you can attach a WB filter to the end of your lens and set the camera using this.

If you are shooting in Raw format, the camera will not make any white balance decisions for you. Instead, when you load your images into photo editing software, you will need to select the white balance tool and click on an area of the photo that should be white. The software will then make the appropriate colour adjustments so that the white area is rendered correctly. In Adobe Lightroom, you can do this in batches, by selecting all the images taken in the same lighting environment at once before using the white balance tool. Alternatively, you could photograph a piece of 18% grey card (available to buy from specialist stores or online) under each of the lighting conditions, then use this to set the white balance.

Alternatively, you could intentionally use an ‘incorrect’ setting for a creative effect. For example, you could use the cloudy setting on a clear day to warm up the tones of your portraits.

One final thing to note is that coloured surfaces reflect coloured light. If you photograph a subject near a bright red wall, for example, then the side of their face nearest that wall will be tinted red, too. To avoid this, you could use only white surfaces near your subject, photograph your subject with the coloured wall behind them or convert the image to black and white afterwards.