Flash Jargon Explained

In our article Flashguns: different types explained, we explored types of flash such as hotshoe.  Here we provide a guide of jargon you might need to understand when delving deeper into the different features of a flashgun.

GN- Guide Number

Guide Number indicates flash power (how far it will reach at a certain aperture and ISO). The higher the figure, the more powerful. If you divide the number by the shooting distance (in metres) you’ll get your working aperture (or, divide it by your aperture to get your shooting distance).

TTL - Through The Lens

Through The Lens flash metering matches the exposure with the info taken by the camera’s sensor to provide the perfect flash output and exposure.

Wireless slave compatibility

This lets the flash control one or more off-camera units, or slaves, sharing selected shooting data for a coherently managed portable lighting set-up without wires.

Swivel and Tilt

Some units have heads that swivel sideways and tilt up, allowing you to bounce the light off a ceiling or wall to give a softer light.

AF Assist

The flash can supplement the camera’s own illumination to provide more accurate autofocus at longer distances and when shooting in lower light conditions.

Diffuser

A diffusion device built into the flash to increase the spread of the output to cover wideangle lenses.

Zoom head

Concentrates the energy of your flash when using telephoto lenses. Motorised zooms automatically alter the coverage to match the focal length of your lens.

FP Sync 

FP mode allows flash photography at any shutter speed by using a rapid pulse of light instead of a single burst, in order to illuminate the scene as the shutter travels across the sensor plane.


Now, test your knowledge by viewing our range of flashgun reviews to find a flash that suits your needs.



This article first appeared in What Digital SLR, buying guide by What Digital Camera magazine