Robert D Feinman

Getting the Blue out of Shadows

Here is the original of a sidewalk cafe in San Francisco taken with a Noblex swing lens camera.
It has been reduced for the web.
Notice that the black and white checkerboard floor is black and blue.

We use select color range to pick just the color of the white tiles.
We set the fuzziness high enough so that similar colors in the shadows are selected as well.
The amount to be included is a matter of taste.

Next we create an adjustment layer using curves and set the white tile to neutral using the grey eyedropper.
The three curves are as follows:

The resulting image is corrected for the blue shadows only. The rest of the colors are unchanged.
In reality shadows are blue, since they are lit by the sky, not the sun.
Most people don't notice this, however and the modification shown here seems more natural.