High-speed sync (HSS) is a game-changing tool for mastering flash photography in challenging lighting situations. If you’ve ever struggled with motion blur or overexposure outdoors, this technique offers a solution to take control of your images.
Coming to you from John Gress, this practical video breaks down the mechanics and benefits of HSS. High-speed sync allows your flash to fire at shutter speeds faster than your camera's sync speed, typically capped at 1/200th or 1/250th of a second. Without HSS, using faster shutter speeds with a flash creates dark bands in your images. HSS avoids this by pulsing the flash rapidly, acting like a continuous light source. This feature is particularly useful for outdoor portraits where you want a shallow depth of field with a wide aperture, like f/1.4, while maintaining proper exposure.
The video also highlights why HSS is essential for freezing motion. In bright conditions, action shots often demand fast shutter speeds to capture crisp details without blur. High-speed sync lets you pair those shutter speeds with flash, ensuring your subject is well-lit even in broad daylight. However, it’s important to note that HSS reduces flash power. This might require adjustments to ISO or aperture, especially at extreme shutter speeds like 1/8000th of a second.
The setup for high-speed sync is straightforward but depends on your gear. Gress emphasizes confirming compatibility between your camera, flash, and trigger. Some systems enable HSS automatically when you exceed your camera’s native sync speed, while others require manual activation in settings. Understanding your specific equipment is critical to making the most of this feature. Adjusting settings like aperture, shutter speed, and ISO based on your creative goals is the next step to achieving a balanced exposure.
The technical explanation of how HSS works is simple: the flash fires multiple bursts of light as the shutter moves across the sensor, aligning these pulses with the open part of the shutter. This synchronization lets you shoot at fast speeds without the limitations of standard flash photography. Check out the video above for the full rundown from Gress.
If you would like to continue learning about how to light a portrait, be sure to check out "Illuminating The Face: Lighting for Headshots and Portraits With Peter Hurley!"
As a pro-photographer with medium format cameras, my leaf-shutters, built into the lenses, had a flash-sync at ALL speeds. It was great at wider apertures for individual outdoor portraits.