Making Beautiful Portraits Using Flash and High-Speed Sync (HSS)
High-Speed Sync (HSS) is a powerful technique that allows you to use your flash at shutter speeds faster than your camera's standard sync speed (usually 1/200th or 1/250th of a second). This opens up a world of creative possibilities, especially for outdoor portraiture in bright conditions. Here's a breakdown of how to achieve beautiful portraits using flash and HSS:
1. Understanding the Basics:
* Sync Speed: Your camera's maximum sync speed is the fastest shutter speed you can use with flash without encountering black bars in your images.
* High-Speed Sync (HSS): HSS allows you to use shutter speeds *faster* than your sync speed. It works by firing the flash in a series of rapid pulses instead of a single burst. This means the flash illuminates the scene continuously as the shutter curtain moves across the sensor.
* Why Use HSS?
* Overpowering the Sun: Shoot wide open (low f-number) in bright daylight to achieve shallow depth of field without overexposing the scene.
* Freezing Motion: Use faster shutter speeds to freeze movement, like hair blowing in the wind.
* Creative Control: Control the ambient light independently of the flash.
2. Gear You'll Need:
* DSLR or Mirrorless Camera: With manual mode and a hot shoe.
* External Flash: With HSS capability. Look for flashes marketed as "HSS compatible" or "FP Mode".
* Wireless Trigger (Recommended): Provides more flexibility and allows you to position your flash off-camera. Make sure the trigger is also HSS compatible. Popular options include PocketWizards, Godox X series, Profoto Air Remote, etc.
* Light Modifier (Optional, but Recommended): Softbox, umbrella, reflector, beauty dish - these help shape and soften the flash's light.
* Light Stand (If Using Off-Camera Flash): To hold your flash and modifier.
* ND Filter (Optional): In extremely bright conditions, even HSS might not be enough to control the ambient light. An ND filter reduces the amount of light entering the lens, allowing you to use wider apertures.
3. Camera Settings:
* Mode: Manual (M)
* ISO: Start at your camera's base ISO (usually 100 or 200) and increase it only if necessary. Lower ISO = better image quality.
* Aperture: Choose an aperture that gives you the desired depth of field. For shallow depth of field (blurry backgrounds), use wider apertures like f/1.4, f/2, or f/2.8. For more in focus, use smaller apertures like f/5.6 or f/8.
* Shutter Speed: This is where HSS comes in. Set your shutter speed *faster* than your camera's sync speed. Start at 1/500th or 1/1000th of a second and adjust as needed. The faster the shutter speed, the more the flash will have to work to provide adequate illumination.
* White Balance: Set to Daylight or Auto. You can adjust in post-processing if needed.
* Metering Mode: Evaluative/Matrix metering is generally fine.
4. Flash Settings:
* Mode: Set the flash to HSS mode (usually indicated as "HSS" or "FP" on the flash).
* Power: Start with a low power setting (e.g., 1/32 or 1/16) and adjust as needed. HSS mode reduces flash power significantly, so you'll likely need to increase it.
* Zoom: Adjust the flash zoom to match your lens. This concentrates the light and makes it more efficient.
* TTL vs. Manual: You can start with TTL (Through-The-Lens metering) to get a starting point, but for consistent results, switch to manual mode and fine-tune the flash power.
5. Shooting Technique - Step-by-Step Guide:
1. Compose Your Shot: Find your composition and frame your subject.
2. Meter the Ambient Light: Without the flash, set your aperture and shutter speed to properly expose the background. Aim for a slightly underexposed background. This will help your subject "pop."
3. Turn on Your Flash & Trigger: Ensure both are powered on and communicating. Set the flash to HSS mode.
4. Set Flash Power: Start with a low power setting and take a test shot. Evaluate the photo on your camera's LCD screen.
5. Adjust Flash Power:
* If the subject is too dark: Increase the flash power.
* If the subject is too bright: Decrease the flash power.
6. Fine-Tune: Adjust your shutter speed and flash power until you achieve the desired exposure for both the subject and the background.
7. Light Modifiers (If Using): Position your light modifier close to your subject to create soft, flattering light. Experiment with different angles to see how the light changes.
8. Focus Carefully: Use single-point autofocus and focus on your subject's eyes.
9. Shoot and Review: Take a series of photos and review them on your LCD screen. Adjust your settings as needed.
6. Important Considerations and Tips:
* Flash Power Loss in HSS: HSS significantly reduces flash power. You'll need to use higher flash power settings and potentially increase your ISO slightly. This is why a powerful flash is recommended.
* Battery Drain: HSS drains flash batteries much faster. Make sure you have extra batteries on hand.
* Ambient Light is Key: The key to using HSS effectively is to control the ambient light with your aperture and shutter speed. The flash is then used to illuminate the subject.
* Distance: The distance between your flash and your subject will affect the light intensity. The closer the flash, the brighter the light.
* Practice, Practice, Practice: Experiment with different settings and lighting scenarios to get a feel for how HSS works.
* Post-Processing: Slight adjustments to exposure, contrast, and white balance in post-processing can further enhance your portraits.
7. Creative Applications of HSS:
* Backlighting: Use HSS to create beautiful backlit portraits with shallow depth of field. Position your subject with the sun behind them and use the flash to fill in the shadows on their face.
* Freezing Action: Capture action shots with a fast shutter speed and flash. For example, you can freeze hair blowing in the wind or a child jumping in the air.
* Silhouettes: Create dramatic silhouettes by underexposing the subject and using the background as a bright, blown-out backdrop.
Troubleshooting:
* Black Bars: If you see black bars in your image, your shutter speed is faster than your camera's sync speed and HSS is not enabled properly on your flash.
* Underexposed Images: Increase flash power, lower your shutter speed (within the HSS range), or increase your ISO.
* Overexposed Images: Decrease flash power, raise your shutter speed (within the HSS range), or lower your ISO.
* Harsh Light: Use a light modifier to soften the light.
By understanding the principles of HSS and practicing these techniques, you can create stunning portraits in even the brightest lighting conditions. Good luck!