In this lesson, I want to show you how to start recognising light and dark relationships in a landscape.

Once you ‘see’ how the light falls on the main masses, such as the ground, trees, and mountains, painting the values accurately will be much easier.

I first encountered this simplification of the Four Planes of Landscape Painting in Carlson’s 1929 book ‘Carlson’s Guide to Landscape Painting’.

I’ve found it’s a surprisingly helpful way of stopping and accessing what you’re looking at in terms of groups of planes of masses and simplifying the enormous detail and overload you can face when painting outdoors.

Understanding how light interacts with the landscape can transform flat canvases into lifelike scenes with depth and realism.

Detail over Depth

Painting the details on a tree, trying to capture the flow of water, and adding highlights to sparkling water can be the most attractive elements of landscape painting.

However, relying on your intuition to ‘feel your way’ can easily result in a loss of basic tonal structure.

The 4 planes help to solve this by giving you an understanding of light.

To illustrate this, first things first; we’re getting the glue gun out!

Modelling the 4 planes of Landscape painting

Here’s a basic three-dimensional model of a simplified landscape.

There is a tree, a bush, a sky, and a hillside.

All elements are white foam core and have a white local value.

You can see this change in value when we orientate them at different angles to the light source.

“The key to this Theory of Angles is, then, that the big elements with which the landscape painter has to deal are, first of all, light masses and half-dark masses, no matter in what sequence you name them.” John F Carlson, Carlson’s Guide to Landscape Painting

1. Sky plane

This is usually the lightest value. But it can vary on a sunny or overcast day.

2. Ground plane

The ground plane receives the most light from the sky, the next lightest value. (There are exceptions, such as snow and bright reflections)

3. Slanted plane

The slanted plane is for hills and mountains; it reflects less light than the ground plane and is darker.

4. Upright plane

This includes vertical surfaces like trees and buildings. This plane is usually the darkest.

Once you have a visual concept of these planes, you can more easily manage tonal values and create depth in your landscape painting.

I’ve made a short 45-second video that illustrates the concept. (You can also watch the video on Youtube here)

“These masses or elements are light or dark, or half-dark or half-light, not because of any colour cast they may have, but because they present different angles to the light that falls upon them from the sky”

John F Carlson, Carlson’s Guide to Landscape Painting

Next time, we’ll try this theory with a landscape painting.