All you need to know about your smartphone’s white balance

Get it right with white.

Have you ever thought you’re whites aren’t white enough? No, don’t worry, this isn’t an advert for washing powder, this is about the temperature of your lighting and why exactly it’s measured in Kelvins.

There is a lot of hardcore science involved in why one colour is a bit blue and another a bit more orange, but as a user interested in the artistic output rather than the scientific reasoning, I’m going to concentrate on the practical realities of white balancing your smartphone photos.

A little bit of background

Colour temperature is the measurement of the colour of a light source. It is measured in Kelvin (K) and named after the Baron Kelvin, William Thomson, (1824 – 1907) who worked on the first and second laws of thermodynamics and also determined the correct value for absolute zero. Baron Kelvin was not only a genius scientist, but also had good photographic credentials for in 1899, he was elected as Vice Chairman of the British division of Kodak Limited.

What colour is light?

All light sources have a colour temperature. Those with a colour temperature closer to direct sunlight appear as white (around 5000K); those with a lower temperature have a red or yellow hue (warm colours); and those with a higher colour temperature appear more blue (cool colours).

Thinking about your light source

The next time you are about to take a photo, have a quick think about where the light is coming from? Are you indoors? And, if so, what sort of lighting is there? If you’re outside, is the light bright sunlight or diffused overcast light?

Back in the day, these considerations would have to be made well in advance. Photographers either had to arrive with a range of film types or a set of filters to counteract the type of lighting they might encounter. These days, due to our uber-clever digital devices, these changes can be made in the press of a button. Not only that but all digital cameras have the capability to work off an auto white balance based on the most likely lighting conditions – usually somewhere between 3000K and 7000K. 

So, how does this effect us taking photographs with our Nokia smartphones?

Here are four photographs taken with the Nokia 808 PureView. The scene is lit with a tungsten studio lamp (around 3200K). As you can see, the auto white balance copes quite well with this light source, since it no doubt falls well within its auto capabilities. Both of the artificial white balance settings, (fluorescent and tungsten) also produce acceptable images. However, the cloudy (or overcast) setting can not cope with this light source and turns the image orange.

Here’s the same set of shots again, but this time lit from natural (albeit indirect) sun light. Once again, the auto setting copes admirably with the light source and is almost impossible to differentiate from the Cloudy setting. But both the Tungsten and the Fluorescent settings, (which would be used for a light source of 2000-3000K), tinge the image blue. This is because the actual light source is already quite blue (probably around 7000K-8000K) and by setting a tungsten white balance, we are more than doubling the blue light the sensor receives.

What does this mean in the real world?

Now we know how the camera judges the whites in a scene we can make a judgement, when necessary, to deliberately override the automatic settings in order to help set the mood or get a more realistic set of colours in our photos.

For example, if you want to create ‘warmer’ images, you can set the white balance to cloudy when you’re in sunny conditions. Or if you want to create ‘cool’ lighting, you could set the white balance to fluorescent in sunny conditions.

There will also be occasions when the auto setting won’t quite give you the correct colours or true whites and knowing how to override it to a more appropriate setting will help you get your whites whiter!

Hopefully, this overview will help you take even better smartphone photos. However, if you have any questions about anything, please ask in the comments below.