09 Aug 2017

What’s so great about soft light?

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Is soft light all it is cracked up to be? Is soft light all it is cracked up to be? Shutterstock

Index

We all love soft light, don’t we? It’s natural and flattering; hard light is old fashioned and looks artificial. And LEDs are a convenient and energy efficient source of soft light that have made most other lights obsolete, particularly if you are on a low budget. Is that all really true?

Well, soft light is natural to the extent that we mostly see the world lit by diffused sources. A cloudy sky, shaded lights, fluorescents tubes and much of the world before our eyes are lit indirectly: light reflected off walls and ceilings. Hard sources in the real world are the exceptions: direct sunlight on a clear day, spotlights, car headlights, projectors, bare bulbs.

And yes, soft light is more flattering on faces, it can wrap itself around the subject in a way that is very appealing. Skin ‘imperfections’ are less obvious, faces become smoother.

Soft light is forgiving

Crucially, it is less easy to make a ‘mistake’ than if you are working with hard light. Put a hard light in the wrong place and you will get ugly shadows, particularly on faces. Put a soft light in the wrong place and it won’t look great, but it won’t be stand out as an error. Soft light is easy.

Soft light is great for a naturalistic drama when you don’t want it to look ‘lit’. Watch hard-lit films and TV from the 60s and 70s, particularly low-budget ones, and they look to our eyes unacceptably ‘fake’. There’s an unnatural sheen to everything, multiple shadows abound, actors seem to have a backlight that follows them wherever they go and light fittings on sets (practicals) cast shadows when they are supposed to be giving out light.

The problems with soft light

But soft light brings its own problems. Firstly, soft light is very inefficient. A soft (diffused) source has to emanate from a large surface area, like through a diffusion frame or bounced off a white reflector, typically, an 8’ by 4’ sheet of expanded polystyrene or foam core. This not only means a lot of light is wasted but the light source itself is, almost by definition, big and awkward.

Soft light is difficult to control; you can’t flag it or focus it. In a small room, a couple of soft sources may just flood everything and the result is something very bland. It’s unlikely to be offensive, but it may just be flat and dull.

Ideally, we want light to be soft without being flat — we want contrast, we want to be able to have inky black shadows as well as that flattering wrap-around softness — and that is almost impossible in small spaces with white walls. Natural is one thing, drab is quite another.

Soft light was once not an option

Because soft light is inefficient, it didn’t really become an option until around the 1980s when film stocks and cameras became more sensitive. In the movie heydey of the 40s, when studios were huge and lenses and film stocks slow (Technicolor had an ISO rating of around 5), 10Kw tungsten lights and carbon arc brutes were essential. To work at those lighting levels with soft sources would have needed an unfeasible amount of power. For this reason, films lit mainly by hard light may look old fashioned or theatrical, but if you try and emulate a classic Hollywood studio look, be warned: those guys knew what they were doing — parodying it is one thing, emulating is another.

Hard light comes from a point source — generally the filament of a lamp or a source that is focussed to a point. This means the lamps are inherently smaller and more efficient.

The most common form of documentary lighting until the turn of the century was open face quartz (tungsten-iodine) lights — ‘redheads’ and ‘blondes’ — as they are cheap, lightweight and give out a lot of light. And heat. Used indiscriminately for classic 3-point lighting (key/fill/back) they look… well, they look like classic 3-point lighting — the shot looks ‘lit’.

The magic of hard light

But here’s the great thing about hard light: it can be magic. It accentuates colours and textures, objects snap into life.

Not only is it efficient, but you can park your light a long way away from your shot and your foreground and background have relatively similar light levels. Do this with a soft light closer to the scene and the light will fall off noticeably. A strong light, further away, creates more even lighting than a weaker source closer to the subject.

It is often said that you can think of the art of a DoP as deciding where the shadows are — it is more about taking light away than adding it in. You can have fun with hard light, you can control it. Barn doors help control where the light falls and flags will cut the light cleanly, creating hard shadows exactly where you want.

You can play with those classic film noir tricks: shafts of light through blinds and shutters and looming silhouettes. You can create drama.



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Roland Denning

Roland Denning is an independent filmmaker and writer based in London. He was a lighting cameraman/ documentary cameraman for two decades, shooting everything from feature drama to rock promos. He still shoots when he can't afford to employ anyone else. His satirical novel, The Beach Beneath The Pavement was published in 2011.

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