What is white balance and why is it important in photography?
White balance is the process of matching your camera to the temperature of the light used to capture a photograph.
Light is the basic component when making a photograph. One could simply describe a photograph as a recording of the light in front of the camera. A camera is, simply, a device that captures light particles (photons) and record them on some type of media. That media could be film or in a digital camera a sensor.
Something that we don’t really think about when we talk about light is the light temperature. A source of light can have different temperatures depending on the type of light. This temperature is measured by a unit called Kelvin. Before we get into all the technical stuff about light let’s try and visualise this in a very simple way.
Let’s imagine a scene. In your mind try to visualise an old fashion library. Something that would not look out of place in a Harry Potter movie. It would probably use candles as a source of light. In a scene such as this, the light would probably be very warm. When we refer to lighting being warm, we’re talking about the colour of the light being more towards the orange side of the spectrum. Most old fashioned light bulbs are also considered a warm light source. The opposite side of these would be a cool light. Cool light tends to be on the blue side of the spectrum. An example of blue light would be the type of light cast by the moon.
Most of us are unaware of this colour temperature in the light because our eyes automatically adjust to the temperature and so we cannot tell the difference. As you go about your day it all looks like it’s one type of light. The truth is that your brain is tricking you. If you were to look at a piece of white paper using a very warm light a white piece of paper would actually look orange. If you were to look at the same piece of paper on the cool light, that same piece of paper would actually look blue. In a practical sense though, whatever the colour temperature of light , to us, that piece of paper looks white.
As I mentioned earlier the temperature of a light is measured in Kelvin. Below is a chart showing you the different values in Kelvin and an indication of the colour of the light.
Cameras see light very differently to the way we humans do. They don’t really have a brain that can translate automatically the type of light being used and automatically adjust it. That’s not to say that they haven’t tried. Most cameras these days have an automatic white balance setting that tries to do this for you, however it is far from perfect and not something you want to trust if you want to get it right.
To get around these, camera manufacturers give you a selection of things that you could choose from to set your white balance. These include, daylight, shade, cloudy, etc. This is a much more accurate way to set your white balance. The other benefit is that if you shoot more than one photo then the white balance of all those photographs is going to be the same. This is going to make your editing much easier and quicker.
So why is white balance so important? Well, if you get the white balance wrong, you might end up with photographs there a little bit too orange or they are a little bit too blue. Now, this is where things get a little bit interesting because we’ve reached a fork in the road. What I mean by that is this. Getting the white balanceright in your camera may not actually matter at all. It all depends if you are shooting RAW images or a compressed type of image such as a JPEG. RAW images allow you to change the white balance during your editing. JPEG images programs the white balance settings into the file. This makes it extremely difficult or impossible to change the white balance of your photograph when shooting JPEG images.
This is one of the reasons why I recommend to everyone to shoot in RAW mode. A few years ago there was still a valid reason to shooting JPEG versus RAW. The size of a RAW files where much larger than that of a JPEG and in order to conserve space on your memory cards , some people would shoot JPEG files instead of RAW. The other reason people would shoot JPEG versus RAW is that if you’re shooting in rapid mode, your camera will stop once your buffer was full. The buffer would then have to write all those files to the card and that whole process would lock up your camera until it finished. These days cards are very fast, very affordable and have a very large capacity so there’s no really valid reason to be shooting JPEG anymore.
So considering that you can change the white balance of your photos during your editing, do you really have to worry about white balance at all? The answer is, it depends. It depends on how accurate the photograph needs to be when compared to the actual scene. If you’re photographing a product and we need to show the actual colours of that product, then getting the right white balance is critical. If you are photographing your nephew’s birthday party, then maybe it’s not so critical.
So how do you determine the colour temperature of a scene? This is actually easier than it sounds. Now, there are many product available they claim to be able to calibrate your photos to make them 100% accurate. In my product photography I use some of these products. The one that I use is the colorchecker passport.
For me this product nails the colour reproduction and the white balance of the scene very accurately. If you don’t need such level of accuracy though, there are much cheaper or free ways to do this. All you have to do is to have something in your photograph of a neutral colour. What is a neutral colour? Well, a white piece of paper is considered a neutral colour. A grey card is also something that can be used and is very inexpensive. Taking a photograph with something that is of a neutral colour in the scene is referred to as a reference shot. The idea is that you take one of these shots with the white paper or grey card in the photo for every scene before you start shooting all your photos. There are functions within Photoshop and Lightroom and allow you to automatically correct the white balance of a photograph by simply telling Lightroom or Photoshop what that neutral colour is. Practically speaking, you click on the white balance eyedrop tool in Photoshop , and just click on that white piece of paper in your photograph. Photo shop will do the rest. Lightroom works exactly the same way. If nothing else convinces you to shoot raw, once you go through this process you will never look back. So whereas in the past we had to be really careful to make sure we have the right white balance set in our cameras, today, we just need to make sure that we shoot in RAW and we have a way to calibrate the white balance during our editing.
What balance has artistic uses as well that we will discuss in a future article so if you don’t want to miss out on that make sure that you visit the site regularly.
If you would like to learn more about contrast or any of the other functions in Adobe Lightroom make sure you check out this link to A Beginner’s Guide to Adobe Lightroom: Interface and Settings