An introduction to White Balance
In this blog, we explore the topic of White Balance; what it is, why it matters, and how to use it properly.
possible that you've never heard of White Balance, or come across your camera's White Balance setting. The reason for this is that modern digital cameras do a pretty good job of making sure that most of the time it doesn't matter! But if you've ever thought that your photos have a strange orange or blue colour cast, but not sure why or what to do about it then read on!
What is colour temperature?
You might have noticed that light can have a different colour to it. The light from mid day on a summer's day is quite white and neutral, however, light from incandescent bulbs, or in the golden hour before sunset can appear quite orange (we refer to this as 'warm' light) and shady areas, or the light in the 'blue hour' just after sunset can appear more 'blue' (this is often referred to as 'cool' light). What you are witnessing is a basic property of light called its 'colour temperature'.
Colour temperatures is measured in units of Kelvin (K); a neutral colour temperature (sunlight at noon) is around 5200K to 6000K. An incandescent light bulb (warm orange light) has a colour temperature around 3000K and shade (cool, blue) has a colour temperature around 8000K. This is the reason that camera flashes emit light of around 5200K to 6000K, to try and mimic the neutral light of a midday sun.
Your eyes are very sophisticated and are constantly compensating for the changes in the colour temperature, so that the world around us looks a 'normal' colour. Cameras have sensors which measure the colour of light, and attempt to do the same as our eyes in showing colours colours correctly, however as cameras are not as sophisticated as our eyes, this can sometimes go wrong.
In the image sequence below, the centre image has been taken with a neutral colour temperature; this was how the scene actually looked to the eye. The image on the left has been given a cooler (blue) colour temperature, and the one in the middle a warmer (orange) colour temperature. As you can see, this has given a rather unnatural colour cast (whites appear blue in the left hand image and orange in the middle image). The right hand image (having the correct colour temperature which matches the light) appears the most realistic with whites appearing to be white.
What is White Balance?
Like your eyes, your camera is designed to try and detect the colour temperature of light and produce an image which reflects it correctly. To do this it attempts to ensure that whites appear white; it does this by adding the opposite colour, so if the light is a little orange it will add blue to bring whites back to neutral without a colour cast. Similarly if the light is a little blue it will add orange. This process is called White Balancing (or White Balance)
What does this mean for your camera?
As described above, your camera needs to detect the colour of light, and carry out a white balance to make sure that images do not have colour casts caused by incorrect assignment of colour temperature. Your camera should have a White Balance option (often abbreviated as WB) setting somewhere in the menu (the option on my Sony camera is shown in the photo below)
Once in the White Balance menu, the options that you have will depend on your camera, but may include the following:
Auto White Balance (AWB): In the mode, your camera senses the colour of light and attempts to perform the appropriate white balance so that photos remain neutral (whites remain white). This is the best setting most of the time, and definitely the best for beginners.
Daylight: For daylight (normally neutral light) situations
Shade: For taking photos in shade, where the colour temperature is usually rather cool (blue)
Cloudy: For cloudy days
Flash: For when using a flash gun.
Incandescent light: For taking photos under incandescent lighting
Custom WB: This allows you to set the colour temperature precisely by entering a colour temperature value (in Kelvin)
When NOT to use Auto White Balance (AWB)
Although it's sensible to use Auto White Balance (AWB) almost all of the time, there are some specific times when it is useful to use one of the other settings. Some examples are:
- When shooting sunsets, your Auto WB setting may try and neutralise the lovely orange colours of sunset a little too much, so using the Shade or Cloudy White Balance mode may give better results
- When shooting the night sky, cameras often struggle to set the correct White Balance to give realistic colours, so it's often better to set a Custom White Balance (of 5500K)
- If your camera is not getting the white balance right, and your images have a colour cast.
The power of RAW
White Balance is yet another reason to shoot your photos in RAW not Jpeg (see this blog article for a discussion of Raw versus Jpeg) as in Raw format files, it is very easy to adjust colour temperatures in post processing software such as Adobe Lightroom. One Lightroom feature allows you to click on an area that is meant to be white, and Lightroom will adjust the whites to be neutral (and adjust the rest of the image accordingly). Trying to change colour temperature on Jpegs can give strange results, so if you shoot in Jpeg and the white balance is wrong, there is little that can be done about it.
Want a learn more?
If you're a beginner photographer who is local to East Devon and want to learn the art of landscape photography, check out my range of local photography courses. Alternatively why not make a weekend break of it and attend one of my residential photography workshops - either my beginners landscape photography masterclass for those starting out in photography, or my intermediate photography masterclass for those who already understand the basics and want more practical help progressing their landscape photography.