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Having flash at your disposal can be invaluable on many occasions, and modern automatic systems make it easier than ever to use.

Most cameras now have a built-in flash, but it’s something to use with care. Set onto auto, the camera will be popping a flash into just about everything, trying to produce a uniformly ‘normal’ picture every time, and that’s not the way forward for a creative photographer. However, the ‘fill-in’ flash works well in automatic to supplement ambient (existing) light. If you practise and study your camera manual you will be able to use it imaginatively as well as usefully.

Flashguns

As well as the built-in flashlight, the manufacturers all make separate dedicated flashguns. ‘Dedicated’ means that when they are connected to the hot shoe on the camera they can be controlled from it and work with the through-the-lens (TTL) automatic exposure. Check your manual for the maximum recommended shutter speed that will synchronize with your flash; you can use slower speeds, but if you exceed the maximum speed you will not get an image.

Flashguns have a very short flash duration which is so fast it will freeze almost any moving subject. They have more power than the built-in flash, and because they have their own battery power, they don’t drain the batteries of the camera. The swivel head can be angled to bounce light off walls or ceilings, which makes a lovely soft light – but be careful that the surface you are bouncing off is neutral, preferably white, or your flash will pick up the colours and cast them onto your subject.

There are many accessories such as diffusers, reflectors and colour filters available for flashguns. They become a really versatile and creative light source when you add an off-camera cable which connects the flashgun and the camera hot shoe, enabling you to light your subject from almost any direction (see pp.116-17), with the flash still dedicated to your camera’s automatic exposure.

This young horsewoman was too strongly side-lit by the sun. I set the camera to P (program) and the camera did a perfect fill-in flash. JG

Flash button

Hot shoe

Flashgun

To calculate the correct exposure for flash when using manual mode, you will need to get the guide number from the instruction manual for your particular flashgun and follow the instructions on how to calculate the f-number.