Raking light is the standard for a range of surfaces
A glancing angle of light throws even small surface irregularities into sharp relief
For almost any formal photographic quality there’s a classic treatment, and in the case of texture it’s when the light source, typically the sun, strikes the surface at an acute angle, hence the term ‘raking light’. It works on anything with a slightly roughened surface, and best of all when that surface texture is a little too fine to register under ordinary, flattened light. If you’ve ever tried searching for something tiny dropped on the floor by shining a torch horizontally, you’ll appreciate why it works.
Ultimately, it’s the play of light and shadow that helps to convey texture, and while raking light is something of a cliché, it really works. You still need to take into account the kind of texture you’re dealing with, though, and this varies hugely from subject to subject. Raking light works for textures of fine-to-medium roughness, but with a bumpier, larger-scale texture it can create too many shadows that disrupt any sense of texture. And with very smooth textures, it’s a very different game altogether – see page 80.
Above are three examples of different textures at different scales, from a building facade to a close-up of a compressed cake of tea. What they have in common is that they’re all lit by a single raking light source that helps to reveal texture and detail.