WHITE BALANCE

There are several photographers who are mystified by the term White Balance. So, what exactly is White Balance? How does it help us?

- Rohinton Mehta

Is it necessary to set the ‘correct’ WB? What happens if we set a wrong WB for the scene we are photographing? Let’s try and answer these questions.

Let us say that you are photographing a person who is wearing white clothes and you are photographing the subject under yellow coloured light. Will his white clothes remain white? No. His white clothes will appear yellowish (unless you have adjusted the WB). We say that the subject has a ‘yellow colour cast’.

Similarly, as an experiment, you light up one side of a subject’s face with blue light and the other side of the face, with red coloured light. The face will exhibit one side as blue and the other as red. These experiments tell us that whatever is the colour of the source of light, will be the colour in the photo. If you photograph the Taj Mahal in the late evening hours, the white Taj Mahal will appear yellowish. So the question is, do you want to show what your eyes saw when you took the photo (yellowish Taj), or do you want to show the actual (white) colour of the Taj? If you prefer the later (original colour), then you would have to remove the yellow from the Taj. This is exactly what White Balance does.

So we can sum it up this way: White Balance is the correction applied to make a scene appear to have been shot in neutral coloured light even though the original scene was shot in coloured light.

Digital cameras offer a choice of various WB settings: Auto, Daylight, Cloudy, Shade, Incandescent, Fluorescent, Flash, and Choose Colour Temperature (the naming can vary with different camera manufacturers).

So far so good.