Auto White Balance

AWBOtto Weiss Bálánscz was a Hungarian sadist from the early part of the twentieth century who used to kidnap photographers and lock them in a basement in Budapest. He compelled them to sit at little windows all day and try to make the light coming through the window into a neutral shade. As they vainly moved sliding controls from left to right and back again, Otto raised and lowered the brightness of yellow and blue lamps. He laughed as they tried to match him. Remember, I said he was a sadist.

The makers of digital cameras, finding that they had circuitry that would do much the same as Otto did, decided to name the function in his honour – this was born Auto White Balance. It may be new but it is still torture.

For a start, auto white balance is not the same between one shot and the next. As the camera continuously calculates changes in light, so it continuously alters what it puts out. Clear grey in one file becomes blue grey or red grey in subsequent shots. You sit at the computer screen and try to match it.

It also can be fooled by lights that subtly change between exposures  – some fluorescent tubes can do this – and the tone differential can be horrifying.

And finally, it can be just perfect – far better at guessing the actual setting than you could be, and far closer to the real colour temperature than even the preset options in the camera menu.

My solution for defeating Otto? If I am in my studio working with my Elinchrom strobe lights I set the camera K balance to 5600º K and bid him defiance. I’ve measured and tested them and they stay at that setting continuously.

If I am out, I give in gracefully and engage AWB in most cases, but keep my options open by shooting a RAW file as well as the JPEG. If Otto has played me false, I can dismiss him later.

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