Seeing the Value Structure in a Landscape
Every landscape you'll ever paint has the same underlying structure. Four planes, four values, one predictable hierarchy. Once you see it, you can't unsee it — and your landscape paintings will never be the same.
This isn't a new idea. John F. Carlson laid it out over a century ago in his book on landscape painting, and it remains one of the most useful frameworks any landscape painter can learn. The problem is that most painters hear about it, nod, and then forget to actually apply it when they're standing in front of a canvas.
So here's how I use it — and how the Carlson's Value Planes tool makes the invisible visible.
The Four Planes
Carlson's insight was simple: in any outdoor scene lit by the sky, surfaces receive different amounts of light depending on their angle. That angle determines their value. And there are really only four categories of angle that matter.
The sky is the light source itself (or the surface facing it most directly). It's almost always the lightest value in the scene. Even an overcast sky is brighter than anything on the ground.
The flat ground — fields, roads, calm water — faces upward, catching a good amount of sky light. It's the second lightest value.
The slanted planes — hillsides, rooftops, embankments — are angled away from the sky. They catch less light, so they sit in the middle of the value range.
The upright planes — tree trunks, building walls, fence posts — are perpendicular to the sky. They receive the least direct sky light and are typically the darkest values in the scene.
That's the hierarchy: sky, ground, slant, upright — from lightest to darkest. It's not a rigid rule. It's a default. And defaults are powerful because they give you something to paint against when you choose to break them.
Why This Matters More Than Color
When most painters set up in front of a landscape, they think about color first. That green, that blue, that warm orange in the shadows. But color without correct value relationships produces paintings that feel flat and disorganized — even when every color is mixed perfectly.
Value is what creates the illusion of light. If your sky and your flat ground are the same value, the scene won't feel like it's lit. If your upright tree trunks are lighter than your slanted hillside, the form relationships break down. The painting looks "off" and most people can't explain why.
Carlson's framework gives you a checklist. Before you worry about whether that shadow is ultramarine or dioxazine purple, you ask: is this plane lighter or darker than the plane next to it? Is the hierarchy intact? If the answer is yes, the painting will read — even if your colors are approximate.
How I Use the Tool
When I'm planning a landscape painting, I load my reference into the Carlson's Value Planes tool and start tagging regions. Sky first — that's usually obvious. Then I look for the flat ground: fields, water, roads. Then the slanted planes: hills, rooftops, anything at an angle. Everything else vertical — trees, buildings, posts — gets tagged as upright.
Open Carlson's Value Planes and load a landscape reference. Tag the four plane types, then check whether the average values follow the hierarchy: sky lightest, upright darkest.
The tool reads the average value of each tagged region and shows whether the hierarchy holds. Most well-lit outdoor scenes follow it naturally. But knowing where your scene deviates is the valuable part — because those deviations are where you need to make conscious decisions.
Maybe your reference has a shadowed foreground that's darker than the upright trees behind it. That's a broken hierarchy. You might choose to keep it for dramatic effect, or you might decide to lighten the foreground slightly to restore the sense of sunlight. Either way, it's a decision you're making on purpose, not an accident you'll discover three hours into the painting.
Testing It on Different Scenes
Carlson's hierarchy holds most reliably in scenes with direct, overhead sunlight — the classic plein air setup. But it's worth testing on every landscape reference you work from, because the exceptions teach you as much as the rules.
Overcast days flatten the hierarchy. The sky is still lightest, but ground, slant, and upright values compress into a narrow range. That's useful information: it tells you the painting will feel quieter and you'll need to be more deliberate about creating separation.
Backlit scenes reverse parts of the hierarchy. When the sun is low and behind the subject, upright planes can catch rim light that makes them lighter than the ground in front of them. That's not wrong — it's just a different kind of light, and knowing you're painting a reversed hierarchy helps you commit to it fully rather than accidentally drifting back toward the default.
Sunset and golden hour scenes push the sky toward warmer, darker values that can approach the value of the ground. The hierarchy still holds in structure, but the gaps between planes compress. Understanding this keeps you from over-separating the values and losing the soft, unified feeling that makes golden hour scenes work.
From Value Planes to Value Map
Once I've identified the four planes in my reference, I often switch to the Value Scale Mapper to get more specific. Carlson's planes tell me the relationship between the four big categories. The value map tells me the exact value numbers within each plane.
After checking the plane hierarchy, open the Value Scale Mapper and toggle to a 5-step view. Hover over each plane to see its exact value number — this is what you'll mix to on your palette.
Together, the two tools give me everything I need to plan the value structure of a landscape painting. The planes tell me the order. The value map tells me the distances. And with those two pieces of information, I can lay in the first pass of a painting with confidence, knowing the light will feel right even before I start refining.
The One Thing to Remember
You don't need to memorize Carlson's exact hierarchy to benefit from it. You just need to remember one question: is every plane in my painting a different value from the plane next to it?
If the answer is yes, your landscape will feel like it has real light. The viewer's eye will move through the space naturally — from sky to ground to hills to trees — because the values are doing the work of creating depth and atmosphere.
If the answer is no, you know exactly where to push. Make the sky a touch lighter. Darken the upright planes. Separate the ground from the slant. Small adjustments to value hierarchy make a bigger difference than any amount of color refinement.
Color gets the compliments, but value does the work. Get the planes right and the painting paints itself.