White balance

When I was using film in the good old days, I don't remember struggling with white balance. In fact, it was unheard of. Perhaps it was because we use black and white film most of the time. Even when we use colour film, white balance wasn't a concern or are we just totally ignorant about it?! With digital photography, we have to know something about white balance.
In this picture, I let my camera handle white balance automatically. However, under the strong sodium light, the white balance went crazy! So, if you cannot get it right and you don't like the colour, make it into black and white.

On my Nikon D3, it is possible to preset white balance very easily. I just need to press the WB button, toggle it to PRE, use a piece of white paper and snap a shot under the light... and it is done! And the above is the result. Suddenly all the colour appears!
However, in certain condition, the automatic WB on the camera is pretty accurate as in this picture.
To be continued...