High-speed sync (HSS) is a technique used in flash photography to synchronize a camera's shutter speed with a flash unit at speeds higher than the camera's standard sync speed. The primary advantage of HSS is that it allows you to use a wider aperture and still control ambient light while using flash. This can be particularly useful in situations where you want to freeze motion or create a shallow depth of field in bright ambient lighting conditions.
Here are some insights on using high-speed sync with ambient lighting control:
Understanding Sync Speed: In traditional flash photography, the camera's shutter speed is limited to the sync speed, which is usually around 1/200 to 1/250 seconds. Beyond this speed, the entire frame isn't exposed all at once due to the movement of the shutter curtains. HSS allows you to exceed this sync speed, typically up to 1/8000 seconds on modern cameras.
Aperture Control: One of the main benefits of HSS is that it allows you to use wider apertures (e.g., f/1.8, f/2.8) to achieve a shallow depth of field even in bright conditions. This is great for portrait photography when you want to blur the background.
Controlling Ambient Light: When using HSS, your camera essentially uses a very fast sequence of curtain movements to expose the entire sensor frame. This means that, even at very high shutter speeds, the entire frame can be exposed evenly. In practice, this allows you to control ambient light exposure while adding flash to your subject.
Balancing Flash and Ambient Light: The key to achieving good results with HSS and ambient lighting control is finding the right balance between your flash's output and your camera's settings. You can adjust the flash power and shutter speed to control the balance between the flash and the ambient light. Slower shutter speeds allow more ambient light in, while faster shutter speeds reduce it.
Use of Neutral Density Filters: In some cases, even at your camera's fastest shutter speed, you may not be able to control the ambient light enough to achieve your desired exposure. In such cases, you can use neutral density (ND) filters to reduce the amount of light entering the camera. This allows you to use wider apertures and slower shutter speeds while maintaining proper exposure.
Practice and Experimentation: HSS can be a bit tricky to master, and it may take some practice to get the hang of it. Experiment with different settings, flash power, and shutter speeds to understand how they affect the final image.
Flash Placement: Pay attention to the position and direction of your flash. You can use modifiers like softboxes or bounce cards to control the quality of light and avoid harsh shadows.
Color Temperature: Remember that the color temperature of your flash may differ from the ambient light. You may need to use color correction gels or adjust white balance settings to match the light sources.
High-speed sync is a powerful tool for photographers, enabling them to create stunning images in challenging lighting conditions. By understanding the technical aspects and practicing, you can achieve full control over ambient lighting while using flash in your photography