On-camera flash

Slot a Speedlight into your camera’s hotshoe and you can really start to explore the creative uses of flash…

The pop-up flash on the camera (if yours has one) is a good place to start with flash, but to get creative with light a dedicated Speedlight is required. On-camera Speedlights are more powerful and allow you control over the direction and quality of light. The ability to angle the flash upwards or swivel the head around gives you the chance to bounce the light off the ceiling or adjacent walls.

Light modifiers

On-camera Speedlights give you access to a range of light modifiers, shapers and diffusers, which can be used for a wide range of creative effects. They are great to use as a large fill light to eradicate shadows, even on the brightest of days.

How far can your flash reach?

Guide number (GN) refers to the maximum output from your flash. GN is usually measured at ISO100. The higher the guide number, the more powerful the flash. If you want to work out the reach of your flash, take the guide number of the flash and divide it by the aperture. For example, a Nikon SB-5000 has a GN of 34.5 metres. If you shoot at f/4 the flash can cover 8.6m (34.5/4 = 8.6). Compare that to a pop-up flash with a GN of 12, the pop-up flash will only cover 3m (12/4 = 3). Increasing ISO extends the reach of your flash. If you raise ISO to 3200, the GN of the SB-5000 effectively becomes 192, giving a range of 48m (192/4 = 48).

Fortunately TTL systems now do all the complex maths for us, all we need to do is fine-tune the flash output with Flash Exposure Compensation.

Bounce & tilt head

Bouncing the light from a ceiling or wall is a good technique to soften light. Large light sources relative to your subject size will create soft light, resulting in fewer shadows. But remember that the flash light will mix with the colour of the ‘bounce’ surface before it reflects back onto your subject. White and silver surfaces are good to use, and light bounced from a gold surface will warm up your subject nicely. Be careful when bouncing from ceilings or walls with strong colours, such as reds or greens, as you might end up with unwanted colour casts in your image.

Flash recycling & ISO

If you are photographing fast-moving subjects with flash, you will need to have a fast recycle time to ensure the flash can fire rapidly enough to keep up with the action. Consider using your flash on a lower power to increase the recycle time of your batteries. You can achieve this by adding an extra stop or two on your ISO, such as by going from ISO100 to 400.

Flash controls

When using on-camera flash, you set your camera up exactly the same as described to control the ambient exposure, then use the Speedlight in either TTL or Manual mode, depending on your subject and scene. Flash Exposure Compensation can be more easily applied from the Speedlight’s controls to fine-tune the output from the flash.