Color Temperature of Light (and White Balance)
What is Color Temperature? What is White Balance?
We will now talk about color temperature and something we use in our cameras called White Balance. But before that, what does color have to do with light? In case you didn’t know, color exists thanks to light. We already talked that light can have direction and intensity. Well, in a sense, light can also have certain color temperature that make things look the color they look. Learning how light works, how is that every visible thing receives light and it can either reflect it, absorb it, let it pass or some sort of combination of all these three, is a topic of its own. A very interesting topic, but in this book I’ll make it very simple for you and skip that part. So let’s continue with light and its color temperature.
Have you ever noted that some pictures turn out slightly yellow or blue? This happens because cameras are not as good as our eyes to adjust how things should look. Some sources of light tend to make things look more of one color than of another. We call this the color or temperature of the light. And just to clarify, in photography, when we talk about color temperature don’t think of weather temperature or touching the light and feeling it hot or cold. Think about colors only. There are warm and cool colors. Red and orange are defined as warm colors; blue and cyan, on the other hand, are cool colors. The light of a candle make things look orange, or in color temperature vocabulary, the light of a candle make things look warmer.
Since light can give your pictures a warmer or cooler color temperature than what it should be, cameras need to adjust that. When your camera fails, you can prevent it or fix it manually. This is done with something called White Balance. So you can think of white balance as a solution to adjust colors. White is the most obvious color to notice whether it has a warmer or cooler tone, so we need to balance it and make it pure or true white. This is why the name White Balance.
Your camera may have the AUTO white balance activated, meaning that the camera decides what the right color temperature for your picture is. But again, it doesn’t always work; besides, you may even want to change the color temperature on purpose for certain effects. This is also why you have the option to turn off the auto white balance and use a different white balance setting to adjust your next shots.
To be honest this is something that I don’t worry too much about. I can always fix the color temperature very easily in my computer. But there are of course those who may feel frustrated when their pictures turn out too blue or yellow and don’t have the software or desire to fix their pictures in their computer. This is why we will discuss it here.
Where is the White Balance in my camera?
White balance is usually labeled as WB on many cameras. Cameras have it in very different places. You may find a dial or a button for it, but I don’t doubt that at least it will also be somewhere on the menu shown on your LCD screen. If you can’t find the White Balance check your camera manual to see where it is on yours. Once you find this option, you will be able to adjust the color temperature in your pictures. If you are using the LCD screen, you will probably see the immediate effect of white balance adjustments on the picture you are going to take. If your picture has a strong non-natural color. You may want to adjust the white balance.
Adjusting the White Balance
Once you have found a way to change your white balance, you will notice that it may either give you names or numbers as your options. It also depends on your camera, but the principle is the same.
Color temperature is measured in kelvins (K). Lower numbers give you warmer colors while higher numbers give you cooler colors. Many cameras, especially DSLR cameras will give you this option to set the color temperature based on these numbers.
Most cameras, however, regardless whether you can choose kelvins or not, these cameras will have some sort of presets or pre configurations for your white balance. You may see some of these symbols below.
Each symbol is for a particular kind of light. Because there are different types of light, there are also different color temperature tones you see on the same object. It all depends of the type of light. Take a look at the chart below to understand what each of these icons do.
[IMAGE Chart of options and/or different WB modes]
Now that you know how to adjust the white balance, you should keep in mind that this adjustment in your camera must be done before taking the picture. A common practice is taking a picture of your subject in the setting first just to see how the white balance will turn out. That’s a quick test. Check that colors are right, if not, make adjustments and take another picture until you get the right color temperature. Once ready now you can take the real picture you want.
Be Professional, But Don’t Worry Too Much About White Balance
As I said before, I don’t worry too much about it because White Balance can also be corrected after I take a picture (this is called post-processing), but here are two things to consider:
JPG format vs. RAW format. If your picture is taken in a JPG format instead of RAW format, (I’ll say more about picture formats later) then you lose some color or image information that will reduce the flexibility to do adjustments. In my case, I take pictures in RAW format and part of the reason is because I leave the white balance in auto and focus on other things such as aperture, shutter speed, framing, etc. And if my picture needs white balance adjustment, then I do it easily in my computer.
Quantity of pictures. If you are taking a lot of pictures of the same subject under the same type of light, you don’t really want to fix every single picture afterwards because they will come out very similar, better fix the White Balance at first and then take the rest of your pictures. But when I say fix, I don’t mean getting too stressed about it. It won’t be the end of the world if your picture doesn’t have the perfect white balance. Especially if you take pictures in RAW format. If you shoot in JPG, and it is only the picture of your life, then make sure you fix the white balance first by taking a picture before your most important shot so you know how the white balance is going to be.
Either way it is a good and professional habit to check once in a while the last picture you took just to make sure you are shooting with the right settings.
Now go out and take a few pictures of the same subject. It can be the picture of a house or a tree. Preferentially something static. Each picture will have only one difference: white balance settings. See below the settings.
Picture 1: This picture should look blue
Picture 2: This picture should look yellow
Picture 3: This picture should have a neutral color
If you want to take things a step further, you can also try to see how your picture looks under each one of your camera white balance settings. Be familiar with all of your white balance options.