Judging colour temperature 2
Part 2 of this exercise looks at White Balance (WB). In the glossary of his 2007 book, Exposure, Präkel defines WB as:
“Adjusting for the colour temperature of the illuminating light, so white and neutral colours appear truly neutral and do not show a colour cast”.
The human eye quickly adapts to different light and will perceive things as ‘white’ that it knows to be white. However, digital cameras process light temperature and colour differently. Most digital cameras do this through an inbuilt WB operating system, which allows the camera’s settings to be adjusted to respond to the colour temperature of the light to aid the reproduction of more accurate colours. For example, a cloudy day has a high colour temperature that can emit a bluish colour cast. Opting to use the Cloudy WB preset compensates for this by adding perceived warmth to the image.
The camera I use, a Nikon D5100, has eight preset white balance options, which include Auto WB, Tungsten, Fluorescent, Daylight, Cloudy, Shade and Flash. It also has a Custom WB option, which I have not yet experimented with.
Judging colour temperature 2
This exercise requires that I decide what colour temperature correction a scene may require, if any. The instructions are as follows;
- Take a similar situation to the last one and shoot the same three kinds of pictures.
- However, you should vary the camera’s WB settings by taking one at Daylight/Sunlight WB setting, another at the Shade WB setting and the third in Auto WB.
- Compare the three versions and note differences and preferences of WB settings
I used the same setting as the previous exercise, an area at the front of my building, using three wise monkeys as my subject. I shot at midday in the sun, midday in the shade and late in the afternoon when the sun was close to the horizon.
1. Midday light
Daylight WB has managed quite well with image 1 as gives the image some warmth without bleaching out the shadows. Shade WB has added an orange/yellow colour cast, which looks unnatural. It did, however bring out more of the red tones in the monkeys and make the details in the shadows more prominent. Auto WB has cooled the image by making the paving stones a pale blue/grey and by darkening the shadow areas on the monkeys.
Overall, I think the Daylight WB did a better job of capturing this scene as it did not add any extra coolness or warmth to the image and captured the colours closest to what they actually were.
2. Midday shade
I placed the monkeys in the midday shade, and took the three shots adjusting the WB as I went. The daylight WB has not coped as well here as with the first situation and the image has taken on a slight pinkish cast. As shaded areas generally produce cooler looking pictures, the Shade WB has ‘warmed’ up the image with a yellow/orange glow, which is a little bit too warm for my taste. The Auto WB is the version I prefer as it while it has given the grey paving stones a slight bluish colour cast, it does not look unnatural.
3. Sun close to the horizon
I took these photographs ½ an hour before the sun was due to set. The Daylight WB has worked well with the orange/yellow low colour temperature light and gives the image perceived warmth. Shade WB has compensated for the blue tones that shaded areas usually hold by adding a strong orange hue to the image. I am undecided as to whether it is too orange or if adds to idea of a setting sun? Auto WB has cooled the feeling of the image and rendered the grey paving stone and the shadows a grey/blue hue. I think a setting somewhere between Daylight WB and Shade WB would be a good WB setting for this scene. I could perhaps achieve this by experimenting with the temperature and tint sliders in the camera RAW processing option in Photoshop Elements 11?
When taking photographs I do adjust the WB settings to match the conditions I am shooting in. However, I now realise that I was doing this routinely with little thought as to how this affects the resulting photographs or how it relates to the lighting conditions. This exercise had also illustrated quite well that lighting conditions can be unpredictable and that other WB settings other that the obvious may actually give more pleasing results. This is something I intend to give more thought to and experiment with in-camera.
Präkel, D. (2007) Basics Photography: Exposure. Lausanne: AVA