Night Work: A Study In White Balance

[Coastal Flyer]

Trying to get a handle on custom white balance and came up with these shots. Each image sampled a different light in the scene. The heavy blue image sampled the sodium vapor street lights. Your comments, please.

CF

[rovowen]

Nice shots, being a newbie, wish you would have explained what you did with each shot.

rovowen

[DEvianT]

Nice shots, being a newbie, wish you would have explained what you did with each shot.

Hi rovewen. As a newbie once myself I'll try and explain what you're seeing above.

Different kinds of light have different temperature. This causes them to appear different colors to our eyes. Us humans being a pretty good design correct for this unconciously. So for example tungsten house light is very orange and warm in color but our eyes make it white.

It gets a bit wierd that hot objects have cool colours and vice versa. So for example a cool colour temperature may have a red hue we'd refer to as warm ironicaly.

Here's a list of some common temperatures:

Sunrise - 2500K
Household light - 3200K
Studio Flash - 5000K
Daylight - 5500K
Daylight Shaded Sky - 7500K
TV Screen - 9300K

If you create a custom white balance like the shots above, and effectively fib about what is white then all the color temps are misinterperated by the camera resulting in color shifts. In the shots above as a different color temp is chosen to 'white' then all other differing color temps shift up or down the spectrum accordingly.

Reference material is here.

[DEvianT]

I'll add flourescent is an exception to this as it sends out all kinds of different wacky colours from all over the spectrum. The result is some weird and wonderful colour casts that are difficult to correct.

[Coastal Flyer]

Rovowen:

What he said.

I sampled a different light source for each shot and created a custom white balance. With each sample the colors of the image change, the most dramatic is the solid blue image which was created when the "white" sample was collected from the extreme orange of the sodium vapor street light.

Hope this helps. The owners manual that came with your camera should provide instructions on how to create a custom white balance. It is quite simple yielding dramatic results, as you can see.

CF

[DEvianT]

When I figure posting images I'll add one I did by altering white balance on purpose to create a color shift on a building.

D

[DEvianT]

Color of buildings was shifted towards white to make the John Lenon image stand out. This was done by stating a color temp about 2000K higher than it should have been when developing the RAW file.

For those that are interested this is the Liverpool Albert dock part of Liverpool's world heritage waterfront. The Liver Buildings can be seen in the background. Light trails are courtesy of a passing number 10 bus on an exposure of about 3 seconds.

[DEvianT]

Rovowen, The moral of the story is never mind the technicalities of white balance go and have a good play and see what a great creative tool it is

[Coastal Flyer]

Having a good time is what it's all about. Having some of the technical insight expands the ability to create new opportunities.

CF