Lesson 4 :: White Balance (Colour Temperature)
At it's simplest, adjusting your white balance gets you the most natural/accurate colours possible.
You may have noticed that when taking photos inside or outside, the colour represented in your photo isn't what you are seeing at the time of the exposure. When we take photos indoors, we are often confronted with darker areas, and thus need to turn on lights to allow more light. These lights are tungsten lights and usually end up causing our pictures to be a bit more yellow/orange than we would like. On the opposite end, when taking picture outside, daylight can make our pictures more blue than we would like. Fluorescents are the devil, and were very hard to compensate for as they cast a horrid green light that we can now adjust for
Let's take a look a scale of light in Kelvins to understand this better:
I won't go too much into this scale, because white balance, as it is, can be a pretty 'stand-offish' topic. But when discussing colour temperature, we say that a photo is either warm or cool depending on the lighting.
So what is happening when what you are photographing is a different colour from what your eye is seeing? Generally, we don't see the difference in this temperature range because our eyes can automatically adjust for it. So unless the colour temperature difference was very extreme, a white sheet of paper will always look white to us. So, because cameras have computers that can't think for themselves, we sometimes have to tell the camera what kind of light we are in to make the proper adjustments to get the natural/accurate colour that we are seeing.
A warm photograph adjusted to accurate colouring by changing the white balance
Adjusting White Balance
If you are doing event work, and moving inside and outside every so often, it's a good idea to change your white balance every time your colour temperature changes. The old school way (and most accurate) is to do a white/gray card setting. To do this, you would take a sheet of white paper (or naturally white material), hold it in front of your camera (filling the entire frame/viewfinder), and manually set the white balance (see your manual for how to do this). This can be very tedious for people moving quickly (because the temperature is always changing), but beneficial if you're staying in one room.
There are some shortcuts thought! Yay presets! Depending on your camera (again), the terminology for this differs, as well as the pretty icons.
Admittedly, unless the lighting in the area is completely crazy I tend to keep my camera on AUTO white balance. The reason for this is that with my work, I change locations so much that changing the white balance would drive me nuts.
Things to watch out for
You will get the biggest headaches from rooms that have large windows if you are photographing with tungsten lights on. This is problematic because you are mixing blue daylight with warm tungsten lights - this is very hard to correct/meter for, and without post processing, will not be balanced completely.
Post Processing
Depending on interest, I can go into post processing at a later date, but adjusting colour temperature has gotten a lot easier in post processing, and almost eliminates the need for while balancing - but let's not be lazy!!! Having correct exposure and colour in camera saves lots of time later on.
More examples of colour temperature correction:
Interior (Tungsten Light)
Exterior (Daylight)
Tungsten preset
Daylight preset
I hope this helps in getting better colours out of your photos!!! In post processing, you can change not just the colour temp, but the overall tonality (green, magenta, cyan, etc.) as well.