Light Through the Day

The tests in the last two chapters lived inside the frame — look at the edge of the shadow, look at where the shadow falls. The test in this one is up in the sky: how high is the sun right now?

Note that the question is not what time it is. A clock is only reliable at one latitude in one season; altitude is the quantity that actually sets the light. Learn to estimate it with your hand — arm out straight, one fist stacked on the horizon is about 10 degrees — and you can judge the light in any city in any month in about three seconds.

Altitude decides three things, and they move together

1. Angle. A low sun arrives from the side and stretches shadows; a high sun arrives from overhead and pins them underneath.
2. Colour. A low sun has to drive its light diagonally through far more atmosphere. Air scatters short wavelengths far more strongly than long ones — scattering goes roughly as the inverse fourth power of wavelength — so blue and violet are thrown sideways out of the beam along the way, and what reaches you is what is left: yellow, orange, red.
3. Hardness. The same long path scatters more light in every direction, so low sun is softer than noon sun, and the tinted sky and clouds become an enormous secondary source of their own.

The difference in path length is larger than intuition suggests. Call the thickness of atmosphere directly overhead one unit; at an altitude of 10 degrees the light crosses roughly six units, and near the horizon more than twenty. Sunrise colour is not a filter effect. The light really did travel that much further.

Which is why “golden hour is beautiful” undersells it: what is actually happening is that angle, colour and softness all improve at the same moment. Warming your white balance buys you one third of it.

Shadow length is arithmetic

There is one formula: shadow length = object height ÷ tan(altitude).

Sun altitude	Length of a person’s shadow	What kind of light
80°	about 0.2× height	Overhead; eye sockets go black
60°	about 0.6×	Still steep; portraits struggle
45°	exactly 1×	The dividing line — light becomes usable
30°	about 1.7×	Good light; form appears
10°	about 5.7×	Golden hour; long shadows become composition
5°	about 11×	Richest colour, but the light is draining fast

Forty-five degrees is a practical watershed: above it, photograph something other than people; below it, portraits and landscapes properly begin. You do not need a table for this either — arm out, four stacked fists is roughly 45 degrees.

Altitude is only half of it — azimuth moves with the season

Altitude sets hardness and shadow length. Azimuth — the compass direction the light comes from — sets which face of the world is lit. And it drifts all year.

The sun rises due east and sets due west on precisely two days: the equinoxes. The rest of the year it is offset:

• At midsummer in London (about 51.5°N) the sun rises well north of east and sets well north of west, tracking a long high arc across the northern sky.
• At midwinter it rises south of east and sets south of west, on an arc that is both short and low.

Across half a year, the sunrise point can slide more than sixty degrees along the horizon at temperate latitudes. The consequences are concrete:

• A north-east-facing wall only catches morning sun in the summer half of the year. In December you can wait all morning and it will never light up.
• An east–west street is only aligned with the setting sun near the equinoxes — which is exactly what makes “Manhattanhenge” a twice-a-year event rather than a daily one.
• The light you photographed in spring can be repeated in autumn. The light you got in June cannot be repeated in December.

So planning a location is half a question about the hour and half a question about the month. Any sun-path app will draw you the arc for a given date; checking before you leave is much cheaper than discovering on arrival that your subject is backlit for the season.

First light: the lowest angle of the day

Morning light and evening light arrive at the same angles, but two things genuinely differ:

• The air is usually cleaner. Dust and particulates settle overnight, so distant detail at dawn is often crisper than the same view at dusk.
• Mist is far more likely. The ground has been radiating heat away all night and is at its coldest just before dawn, which is when water vapour condenses.

Low light plus mist gives you something no other slot can: visible beams. Droplets scatter light back towards you, so the path of the light becomes an object in the frame. It is the same effect the last chapter described — back light makes air visible — turned up as far as it goes.

The costs are that the light changes very fast, and that you must be in position while it is still dark. In practice: arrive forty minutes before sunrise, set up, and wait. The fifteen minutes that matter will not wait for you to walk over.

Blue hour, 20 to 40 minutes either side of the sun

Blue hour is the answer for cities, and it works on a brightness argument. Photograph a city by day and the lights make no impression even though they are on; photograph it after full dark and you have dots of light in a void. For twenty-odd minutes, the two sit inside the same exposure range.

The name comes from the French l’heure bleue, and the window corresponds roughly to civil twilight — the sun between the horizon and about six degrees below it. The blue itself has two causes: the usual scattering, plus ozone high in the atmosphere absorbing part of the orange-red light on the very long path the remaining sunlight has to travel. Together they make this sky a deeper, purer blue than daytime.

Three practical notes:

• Use a tripod. Exposures run into seconds, and they get longer every minute.
• Be set up early. There is no time to change position once it starts.
• Shoot a sequence, not a frame. One exposure every couple of minutes from sunset onwards, then choose at home. The balance point lasts a few minutes, and on location your eyes will lie to you about it — human vision adapts continuously, the sensor does not.

Golden hour

The keyword for golden hour is long shadows. With the light running nearly horizontal, anything with height draws a line across the ground, and those lines are free leading lines and free pattern.

For portraits, light at this angle reaches the face without carving out the eye sockets, and skin renders warm rather than sallow — which is why practically every portrait photographer books this hour.

Three details worth knowing:

• How long golden hour lasts depends on your latitude. Near the equator the sun descends almost perpendicular to the horizon and the whole window can be gone in thirty minutes; in northern Europe in summer the sun slices down at a shallow angle and the same conditions can stretch across two hours or more. Do not carry a habit from one latitude to another.
• Auto white balance fights you. Cameras routinely “correct” away the colour you drove out to wait for. Fix white balance to daylight, around 5200–5500 K, and the gold survives.
• The far side of the subject is a different light entirely. In the same minute, the front-lit side is saturated and warm while the back-lit side is rim light and haze. Five steps buys you a different set of pictures.

Cloud decides whether a sunset happens

Whether an evening produces colour is mostly decided by cloud — and not by how much, but by which layer, and whether there is a gap on the horizon.

• Completely clear: after the sun goes, colour stays in a narrow band near the horizon and the rest of the sky darkens quickly. Clean, but plain.
• Mid- and high-level cloud (cirrus, altocumulus) is ideal: it is high enough that once the sun is below the horizon, light still reaches the underside of it, and the whole sky lights up. The five to fifteen minutes after sunset are often better than sunset itself — which is when most people pack up.
• Low thick stratus: the light never gets in and nothing happens.
• The gap matters most. If there is a clean strip of sky above the western horizon, the last light can shoot through it and strike the high cloud. Without that gap, no amount of cloud overhead will do anything but go grey.

So the question before leaving is not “is it cloudy today” but “is there a gap low in the west, and is there high cloud up there to catch the light?” Both present, it is worth the trip. Only heavy low cloud, and the evening is better spent on another subject.

Noon: the problem is not the clock

“Don’t shoot at midday” is advice that has been simplified past the point of usefulness. The variable is altitude, and altitude depends on latitude and season together:

• At midsummer noon in Taipei (around 25°N) the sun reaches nearly 88 degrees — effectively straight overhead, and the worst portrait light there is.
• At midwinter noon in the same city it is about 42 degrees, right at the edge of usable. Winter middays are good light.
• In London the same two figures are roughly 62 and 15 degrees, so a midwinter noon there is lower than a Taipei mid-afternoon.
• And on the Swedish coast at 58°N, February noon leaves the sun around fifteen degrees up, with shadows more than three times the height of what casts them. For an entire season, local noon looks like our late afternoon.

The correct question is never what time it is. It is how high is the sun — and your hand answers that faster than any app.

When the sun genuinely is high, it is not useless:

• Architecture and geometry — vertical faces are lit evenly, which suits structure.
• Shadow patterns — short dense shadows make strong graphic shapes on the ground, and can carry a picture by themselves.
• Water — the higher the sun, the more light enters the water instead of reflecting off it, which is what you want for shallows and anything below the surface.
• Black and white — when colour is flat, organising the frame by tone works better anyway.

If you must photograph people at noon, the simplest fix is the previous chapter’s: find open shade. The source becomes the whole sky, far softer, at the cost of going blue — and the snow photograph above is the cleanest possible evidence of that shift. Those shadows are not grey. They are blue.

Night

Once it is fully dark, the only light is artificial, and the question changes from where the light comes from to where the lights are. The technical points:

• Raise ISO without hesitating. The X-T5 and X-E4 are entirely usable at ISO 3200–6400. Noise is recoverable; camera shake is not.
• Expect mixed colour temperatures. One frame may contain tungsten (orange), LED (white or bluish) and fluorescent (green). No white balance satisfies all three. Pick the dominant source, correct for that, and let the rest drift — at night, colour casts usually read as atmosphere rather than error.
• Wet ground after rain is a free reflector, extending every light into a long reflection and rescuing the bottom half of the frame from solid black.
• Stand where light is falling, not between pools of it. Composing at night is largely a matter of finding a lit stage.

Six symptoms and what caused them

1. Every midday portrait has black eye sockets → overhead light, sun above about 60° → move into full shade, or move the shoot towards either end of the day; if neither is possible, fill from below with a reflector.
2. Sunset photographs look far weaker than the scene did → auto white balance “corrected” the warmth away → fix white balance to daylight, or restore it from the raw file.
3. Blue-hour frames have a dead black sky → you started too late; the sky had already dropped below the lights → begin twenty minutes earlier and shoot a continuous sequence.
4. Night frames are blurred → shutter too slow without support → raise ISO first, before anything else; on a tripod, switch stabilisation off and use a two-second timer so pressing the shutter does not shake the camera.
5. Distant detail at dawn is washed out and white → not a focus error but scattering in the air, i.e. mist or haze → work close, photograph the beams, or wait for the sun to climb and burn it off.
6. A spot that photographed beautifully one afternoon looks flat the next morning → the altitude may match, but the azimuth is reversed — morning lights the opposite face → to repeat yesterday’s light you have to return at the matching compass direction, not the matching altitude.

The last one is the most common and the least often explained: two moments each day share an altitude, and they light opposite sides of everything.

“Magic hour” is a term borrowed from cinema

The phrase photographers use came out of film production, and it began as a complaint: it named the warm, soft, and very short period after sunset — short enough that a crew could only shoot a few minutes of usable footage a day.

In the late 1970s the cinematographer Néstor Almendros turned that constraint into the entire look of Days of Heaven (1978), shooting a large share of the exteriors in the window around sunset, so the film carries one continuous register of low warm light. It won the Academy Award for cinematography and pushed “magic hour” out of crew slang and into general use.

What deserves attention is the price of that decision: to shoot only in magic hour, an entire crew waited all day for twenty-odd minutes. The same trade applies to you. Good light is not a lucky exception you stumble into; it is something you schedule around. The difference is that you do not have a crew to keep waiting.

A planning table

Decide the subject first, then work backwards to when you leave the house.

What you want	When	Why
Skylines, bridges, lit buildings	20–40 min after sunset	Sky and lights sit at one brightness only then
Portraits in natural light	Sun 10–30°	Low enough not to dig out eye sockets; warm skin
Landscape, hills, fields	The hour after sunrise and before sunset	Long shadows describe the terrain
Texture — old walls, sand, bark	Sun 5–20°	A grazing angle stretches every small shadow
Architecture, geometry	Sun above 60°	Even light on vertical faces, strongest ground patterns
Mist and beams	Within half an hour of sunrise	The likeliest window for fog all day
Street and markets	Overcast, or open shade at any hour	Soft, direction irrelevant, colour clean