Exercise: Judging colour temperature

by Suzy Walker-Toye

The exercises on p136 & p139 are two parts of a whole story about judging colour balance. This function is also know as white balance because it sets the very brightest parts of the scene to pure white. Although I thought I had a fairly good handle on what white balance is (when I’m in the sea I set manual WB see below), when using new functions on my camera I like to know what they do. I most often just leave my white balance set to auto and then adjust it slighting in Lightroom if necessary. For the exercise we are using a Danbo (which doesn’t have a strong colour – he’s amazon cardboard box coloured). First I took a few shoots inside (with no lights on, just available daylight) to check the sorts of looks each setting produces.

As you can see, if you hover the mouse over the thumbnails it lists the white balance (WB) setting selected from the camera (you can click to open them bigger in a gallery but its easier to compare them with the thumbnails). The only extra one I added was the auto white balance which has been auto white balanced in Lightroom. I didnt include the flash ones because this post is related to available light photography and not supplied light such as a flash or strobe.
White Balance sliders in Lightroom 4 White balance is made up of Temperature (measured in K for Kelvin) and Tint and those appear as two sliders in LR. Also you can set similar presets (daylight,cloudy,tungsten etc) in a similar way as you can set in the camera. As shot will use the cameras WB settings. The difference here between the auto white balance in the camera and the auto white balance in lightroom was so minimal I could hardly tell a difference by looking at the pictures. However the camera one was 3900K with tint +18 and the auto one was 3850k with tint +17 which is ever so slightly bluer looking with a touch more magenta.

As you can see, the camera presets have a marked difference (apart from underwater which is frankly just confusing as I was expecting that to be really red, but it seems to be just auto with an extra +1 tint so we’ll ignore that one). The sunny setting warms the whole photo up to 5000k (+5 tint). The shade setting warms it even further 7250k (-1 tint). Cloudy is in between them at 5800k (+5 tint). The next two are for dealing with different types of artificial light, incandescent (tungsten lights to you and me) and fluorescent (like you get in shops and offices). These two sets of lights obviously behave quite differently. Incandescent is way down at 2700K (0 tint) and fluorescent is at 4200k but with a massive magenta tink of +53. While I was googeling to check that incandescent actually meant tungsten I found this really useful link.

Anyway, once I took Danbo outside for the real part of the exercise things got pretty interesting. For this exercise I took shots in the sunlight in the middle of the day, shots in the shade in the middle of the day and shots in the sunlight at the end of the day when the sun was low (sometimes called magic hour because the warm colour of the light makes everything look so nice). Here they all are compared.

As you can see depending on if you’re in the sun or the shade and what time of day it is the white balance presets give you different results. The shady images are more blue than the sunny ones and the low sun ones are a really warm yellowy colour. As you can also see, the LR auto WB has quite a different effect on each bringing it back to neutral colours, although we wouldn’t want to in the case of the low sun because we usually shoot at that time of day expressly for the colour balance of the sun at that time. My favourite one? Well the colour of Danbo in the auto WB magic hour is the nicest but I do like auto WB sunny Danbo too. Which one do you think is the best white balance?

When I’m in the sea using shooting available light I use a red filter (called a magic filter). I have to set the manual white balance to allow the camera to compensate for the filter. The filter goes on the back of the lens like this.
Magic Filter

and I set the manual white balance using my hand like this
Setting the white balance manually

This is a shot where I’ve used a magic filter (in this case I actually manually white balanced on the ship since it was white, and with my larger dome my hand doesnt always fill enough of the frame to get a good reading):

And this is a non-filtered available light shot where I’ve tried to white balance on the sand in LR afterwards, as you can see the sea in the top is also white but the blue has gone a horrible colour.


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