Imagine you want to take a photo – be it in your living room, outside at sunset or at a party. In order to take a picture, your camera needs one thing above all: light.
No light – no picture. It’s as simple as that.
How does light actually get into the picture?
Roughly speaking, you let a certain amount of light fall on the sensor (or previously: the film) with your camera. The three large adjusting screws for this are called:
Aperture, shutter speed and ISO.
- The aperture is like the camera’s eye – the wider open it is, the more light comes in.
- The shutter speed determines how long light is allowed in – the longer, the brighter (but also: the sooner something becomes blurred when something moves).
- And the ISO value regulates how sensitively the sensor reacts to light – however, high ISO values often come at the price of image noise.
So far, so good. Now many are saying:
“Why should I use flash at all? My camera still takes usable pictures at ISO 12,800 – even at night!”
That’s right. Technically speaking, you often no longer need a flash to “just see something”. But photography doesn’t just mean that you see something – it means that you decide how you see something.
Flash is more than brightness
If it’s simply a matter of brightening up the scene because it’s just dark, the flash is usually the worst solution, in such a situation I would rather turn up the ISO.
Who doesn’t know the typical cell phone picture look with flat, bright light, red eyes and shiny foreheads?
That’s the cliché. Lightning = ugly. But it doesn’t have to be!
In reality, a flash is an extremely versatile tool for creating with light. And that brings us to the more exciting part:
What can you do with flash – and why is it exciting?
1. lighten shadows – targeted and discreet
Sometimes you don’t want to brighten the whole scene, but just a specific area. For example, a person’s face that would otherwise be in shadow. A targeted flash pulse can subtly bring light into the picture without it looking “flashed”.
2. create a mood
With flash, you can put light exactly where you want it – regardless of the time of day or weather. For example, you can create dramatic sidelight, make a scene look “cinematic” or set specific accents. You shape the light – and therefore the feel of the image.
3. freeze movement
If you are shooting in low light and your shutter speed has to be slow, you will often get motion blur. At this moment, a flash can “freeze” anything that moves like a brief flash of light – even if the camera would otherwise take a longer exposure.
Flash vs. continuous light vs. natural light – which is which?
Natural light is wonderful – but also quite unreliable. Sometimes the sun shines, then a cloud moves in front of it, then the sun disappears behind a house. Sometimes there is simply too little, and sometimes too much.
Continuous light – e.g. an LED spotlight – has the advantage that you can immediately see how it affects the subject. Great for beginners in particular! However, powerful continuous lighting generates heat, is heavy and requires a lot of power.
Flash, on the other hand, is extremely powerful – you get a lot of light with a short pulse. But you can only see the result in the photo. So it takes a bit of practice to be able to work with it intuitively.
Conclusion: flash is not an emergency nail – but a design tool
The next time you think about using flash, don’t just think about “more light”, think about better light. Flash is not the last resort when it’s too dark – it’s your tool to make your picture look the way you want it to.
