Getting Colour Right

Tutorial and images supplied by
ILEX Press Limited

This tutorial is taken from Getting Colour Right by Michael Walker and Neil Barstow. Click on the book image to be taken to the title information page where you can buy a copy at 20% off the cover price.

MIxed Lighting - Localized Colour Corrections

This looks like a difficult picture to fix. It's a dark, low contrast scan from a desktop scanner with no supplied profile. On top of that, it's got mixed light sources - evening sunlight on the church tower, artificial light on the base of the building and reflected twilight-sky light in the courtyard

First we assign a profile in Photoshop. With none embedded, it's a question of trial and error, but a monitor-based colour space is likely to be the most suitable. ColorMatch RGB for Apple computers or sRGB for the Windows platform

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1. Starting with the Levels dialog, holding down the Alt key, we move the shadow slider, to find where the true blacks are in the image. The doorway at the bottom left looks promising.

We place a permanent sample point (shift-click with the eyedropper), and then check back in the Levels clipping display that it is in the right place (by holding down Alt/Option while moving the shadow slider).

Having confirmed that we picked the darkest spot, we set the shadow dropper to RGB values 0, 0, 0 (double-click on the shadow eyedropper to set the values) as we want a true black here - no detail is needed - and we then click on the permanent sample point.