Golden hour has a reputation as the pretty hour, which makes it sound like a matter of taste, and taste is the sort of thing you can reasonably decide to ignore. It is worth knowing that it is also the easiest light of the day to photograph in. Less gets thrown away, fewer decisions have to be made, and the pictures that come back need less work afterwards. The prettiness is a side effect of the physics, and the physics is one number: how high the sun is.
One number decides all of it
Everything the sun does to a scene follows from its angle above the horizon. Sunlight arriving from overhead passes through a short column of atmosphere, keeps most of its blue, stays intense, and throws a shadow straight down and hard. The same light arriving at five degrees has travelled through roughly twelve times as much air to reach the same place.
That long passage does three things at once, and they are the three things people mean when they say golden hour. It scatters the blue out of the beam, which is what makes the light warm. It dims the beam, which brings the sun closer in brightness to the sky around it. And it spreads the source: what reaches you is no longer only the disc of the sun but a large glowing region of low sky, and a large source makes a soft shadow with an edge you cannot find.
The drawing beside this is the geometry on its own. Shadow length is height divided by the tangent of the angle, which is why it grows so violently as the sun drops. At forty degrees her shadow is a little longer than she is tall. At five degrees it is eleven times her height and leaves the frame.
Why it is easier, not only prettier
Here is the practical argument, and it is the one worth having. A camera can record a fixed span of brightness, somewhere around twelve or thirteen stops on a decent modern sensor and rather less by the time a photograph has been printed or looked at on a phone. That span does not change during the day. What changes is the span in front of the camera.
At noon the sun is the brightest thing available and the shade under a tree is lit only by the sky, so the two are very far apart. Point a camera at both and something has to go: either the sky turns white or the shade turns black, and usually a little of each. You spend the afternoon working around that. You bring a reflector, or a flash, or you take three frames and merge them, or you accept a photograph with a hole in it.
At golden hour the same scene has quietly shrunk. The sun is dimmer, so the lit side comes down. The sky is large and bright next to that dimmed sun, so the shadow side comes up. The distance between the brightest and the darkest thing in the frame is now small enough to fit, and you can point the camera at what you actually wanted to photograph and press the button. That is the whole benefit, and it costs nothing but being there at the right time.
Light that comes from somewhere
A second, quieter advantage: low light is light with a direction. At noon it comes from above, and above is the one direction that flatters nothing. Brows put their shadow over the eyes, the nose lands on the mouth, the chin cuts the neck. It is the lighting of a bad passport photograph, and it is not a settings problem, so no amount of fiddling with the camera will fix it.
When the sun is near the horizon it lights a face the way a window does: from the side, roughly at eye height. One side is lit, the other falls away, and the boundary between them runs down the face. That boundary is the whole trick. A photograph is flat, and the only way it has of telling you a thing has a shape is where its light turns into shadow. Overhead light puts that boundary in small useless places. Side light draws it right down the middle of the subject, where you can see it.
The same holds for everything else, not only for faces. A field at noon is a green rectangle. The same field at seven in the evening has every furrow, rut and tuft picked out, because each one is now tall enough next to the light to cast something. Texture is small shadows, and small shadows need a low sun.
How long you have, and it is not an hour
Golden hour is not an hour, and it is not the same length twice. The usual definition is the period when the sun sits between about six degrees above the horizon and the horizon itself, and how long that takes depends on how steeply the sun is falling, which depends on your latitude and the time of year.
At the equator the sun drops almost vertically all year and the window is a genuine twenty minutes. In Amsterdam it runs from about half an hour at the equinoxes to nearly an hour around midsummer, when the sun meets the horizon at a shallow angle and takes its time about it. Midwinter is generous for the same reason, which surprises people. Drag through the year in the drawing and the shape is clear: long at the solstices, short in between.
Then there is the second window, after the sun has gone, which the piece on the canals is largely about. From sunset to roughly half an hour after it, the sky is still bright and is now the only source, so it behaves like an enormous soft light hung over everything. It is the best twenty five minutes of the day for a city, and most people have packed up and left by then.
What each part of the day is for
None of this makes the middle of the day useless. It makes it a different tool, one that suits some subjects and fights others. The table is the shortest honest version.
| Sun height | What the light does | What it suits | Verdict |
|---|---|---|---|
| Below the horizon | Sky only, huge and soft, going blue | Cities, water, anything with its own lights | Blue hour |
| 0 to 6° | Warm, dim, sideways, shadows without edges | Faces, landscape, almost anything | Golden |
| 6 to 15° | Still low and directional, edges arriving | Texture, long shadows as a subject | Good |
| 15 to 40° | Ordinary daylight, contrast climbing | Anything standing in open shade | Workable |
| Above 40° | Straight down, hard, more range than fits | Shade, interiors, black and white, water from above | Difficult |
| Overcast, any hour | The whole sky is the source, and there is no direction at all | Faces, forests, detail, anything soft | Underrated |
The overcast line is worth its own sentence. Cloud solves the contrast problem completely and charges you the direction for it, so it is wonderful for a face in a forest and dull for a landscape that needed shape.
Using it, in practice
The awkward part of golden hour is that it is short and it does not wait. Everything below is about arriving with the decisions already made, because the light will not give you time to make them.
- Arrive early. Half an hour before the window opens, so that when it starts you are choosing between compositions rather than looking for one.
- Know which way you will be facing. Lit from behind you, the scene is warm and simple. Shooting into the sun gives you rim light and flare, which is lovely and much harder. Pick one before you get there.
- Turn auto white balance off, or put the warmth back afterwards. The camera reads the warmth as an error and corrects it out, and correcting it out is the one thing you did not come for. Daylight or cloudy keeps it.
- Expose for the sky, not for the ground. The range fits now, so a frame that protects the highlights will still have a usable shadow end. This is the habit that midday breaks.
- Watch the shutter speed. The light is dropping fast, and by the end of the window you are two or three stops down from where you started. This is where the ISO piece earns its keep.
- Stay after sunset. The twenty five minutes after the sun goes are frequently better than the hour before it, and by then the car park is empty.
The short version
- Everything follows from the sun’s angle. Low sun, long soft shadows, warm light.
- The warmth is blue scattered out by a long path through the atmosphere.
- The softness is the source growing: a whole low sky rather than a small disc.
- The real advantage is contrast. The scene shrinks to a range the sensor can hold.
- Low light has a direction, and direction is what gives a flat picture a shape.
- Overhead light puts shadows in the worst places on a face, and no setting fixes it.
- The window runs twenty minutes to an hour, longest at the solstices away from the equator.
- Then stay. Blue hour is the second half of the evening, and most people miss it.