I enabled high-speed sync in my camera’s custom functions and had the rider make another pass. Pop! The flash went off as normal, at least to my eye, but the resulting image was jaw-dropping. At 1/1000 sec., my flash had perfectly filled in the shadows on the mountain biker, and the image was tack-sharp. That one shot changed the way I shot action sports.
Digital camera technology changes as fast as the stock market. Every month there seems to be new camera technology or postprocessing techniques that open up new doors in photography. Think about it—HD video capture, ISO 204,800, mirrorless cameras, wireless shooting, iPad compatibility—photography is evolving quickly.
High-speed flash photography fits in this category. First, there was High Speed Sync photography, allowing speedlight shooters the ability to shoot much faster than the standard 1/250 sec. flash sync speed. But then HyperSync was introduced, and now photographers could use studio flash packs at speeds of up to 1/8000 sec. Incredible!
Why all the excitement about high-speed flash photography? Most photographers assume this technology allows you to use flash on fast-moving subjects and freeze the action. This is true, but only the tip of the iceberg! There are many benefits of high-speed flash photography, and every photographer should know how to use it.
FLASH SYNC BASICS
Every camera has a shutter sync speed, the maximum shutter speed the camera can use with flash. For many cameras, this is 1/250 sec., but it can be slightly faster or slower depending on the camera. What happens if you use flash and shoot faster than the sync speed?
Cameras have two shutter curtains moving in conjunction with one another during an exposure. If your exposure is 1/250 sec. or slower, the shutter curtains don’t overlap—one is retracted while the other is moving. But if you shoot faster than 1/250 sec. (assuming this is the sync speed), the rear curtain starts to close before the front curtain has fully opened. If a flash is shot during this exposure, part of the scene will be blocked from the flash illumination. The result is a dark band across part of your image. For years, this meant you couldn’t shoot faster than 1/250 sec. if you wanted to use flash. Then High Speed Sync flash photography was introduced.
TYPES OF HIGH-SPEED FLASH PHOTOGRAPHY
There are two technologies that enable high-speed flash photography: High Speed Sync and HyperSync. High Speed Sync, or HSS, refers to shooting with speedlights, while HyperSync involves shooting with larger flash systems.
With HSS photography, speedlight flash photographers can shoot faster than 1/250 sec. If you’re a Nikon shooter, this ability is enabled in the custom functions. If you shoot Canon, HSS is activated on the flash unit. When HSS is turned on, the speedlight emits a rapid strobic flash burst during the exposure. This ensures that the scene is always getting flash no matter what the shutter curtains are doing. In essence, it’s like illuminating a scene with a continuous beam of light. The flash burst still looks like one pop, but really it’s a pulsating beam of light coming out of the flash. Welcome to the flash revolution! Now you can use your speedlight at any speed, and HSS works perfectly with off-camera wireless flash photography.
Larger studio flash systems use a different technology, but with similar results. Unlike TTL (through the lens) speedlights, which use camera data to determine flash exposure, large flash packs simply pop flash at the selected output. You need to use a flash meter or preview your LCD to determine proper exposure. Similar to speedlights, flash clipping will occur if you shoot faster than the camera sync speed. HyperSync changes the game for flash sync with larger flash systems.
PocketWizard designed HyperSync to be used in conjunction with one of its MiniTT1 or FlexTT5 transmitters. With HyperSync enabled, the transmitters recalibrate the timing between the flash pop and shutter curtains. Unlike HSS, which uses a pulsating flash burst, HyperSync uses just one flash burst. HyperSync can time the shutter release during the "flash tail" after the peak flash burst. The tail, although weaker, is a longer duration of light from your flash unit than the peak. This longer duration of light allows you to use incredibly fast shutter speeds.
I use Elinchrom Rangers, and I can shoot at 1/8000 sec. with my Nikon D300S, the maximum shutter speed for most cameras. (I do get a small band of flash clipping in my images at this extreme speed, which is easily cropped out.) In order for HyperSync to work, you need both a PocketWizard transmitter on your camera and a receiver on your flash pack. The latest software version for HyperSync automatically calibrates the specific camera/flash system.
HyperSync performance varies depending on the camera and flash system used. Some photographers may be able to get 1/1000 sec., while others will get 1/2000 sec. or faster. Generally, smaller-sensor cameras work better than larger-sensor cameras. PocketWizard offers sample camera/flash sync speeds on its website (www.pocketwizard.com). Use the slowest flash-duration head your system offers. I use the slower S FreeLite heads with my Elinchrom Rangers and Quadras to get the best performance.
COMPENSATING FOR REDUCED OUTPUT
Using either high-speed flash method will reduce your effective flash range. With one speedlight in HSS mode, I need to be around 6 feet or closer to my subject for the flash to illuminate him. If I fire multiple fast frames, my flash recycling slows down considerably. To remedy this problem, I use multiple flash units, giving me more power and faster recycling.
My Elinchrom Rangers also don’t project light as far using HyperSync. I’m not getting the full power of the peak flash burst shooting at super-high speeds. I’ll either move my flash closer to the subject or open up my aperture to increase the illumination of my flash. Using a sports reflector on my flash head, I can shoot over 60 feet away at 1/8000 sec. and still hit my subject with flash (using my D300S and an S head), and my Ranger is at about 75% power. I can get more distance at full power.
BENEFITS OF HIGH-SPEED FLASH PHOTOGRAPHY
No matter what method you use to achieve high-speed flash photos, this technology opens up creative options that were impossible before. Try using these techniques on your next shoot.
1. Freeze the action.
Like the name implies, high-speed flash photography allows you to use lightning-fast shutter speeds to freeze the action and use fill-flash. When shooting fast action and using flash, pho
tographers had to rely on flash duration to freeze the action. This meant underexposing the existing light 2 stops or more so the flash was the main source illuminating the subject. Flash durations are very fast and can be over 1/2000 sec., plenty fast to freeze most action.
But what if you just want to add a little fill-flash to a road biker as he whizzes by you? For this image, you’d have both daylight and flash illuminating the subject, but the daylight would be the primary source. If you shot at 1/250 sec., your maximum flash sync speed without HSS or HyperSync, you would get blurry images. But if you enable HSS or HyperSync, you can shoot at 1/2000 sec. and freeze the action in the daylight, and add a little fill-flash.
2. Use selective focus.
Another benefit of using High Speed Sync or HyperSync is the ability to use wide-open apertures with flash in bright sunlight. Say you’re photographing a model in open shade and want to use an aperture of ƒ/2.8 to nicely blur the background. When you establish the correct exposure using ƒ/2.8, you find that 1/1000 sec. is the right shutter speed. And since the model is in some shade, you want to add just a touch of flash on her to liven up her skin tones and add a little more contrast. Since you’re using high-speed flash, you’ll have no problem shooting at 1/1000 sec. You may have to double up your speedlights or move your flash head closer to the subject, but you can still shoot at ƒ/2.8 for that nice background bokeh. I really like to use my 85mm ƒ/1.4 lens with flash. Shooting at ƒ/1.4 almost always means I need to use a shutter speed faster than my normal sync speed of 1/250 sec.
3. Darken the background.
When I shoot outdoor portraits, I generally like to underexpose the daylight by 1 to 2 stops. Underexposing the daylight produces darker backgrounds with more drama and better separation for my subject. Occasionally, I’ll underexpose midday skies 3 stops for a nighttime effect. But to darken the sky this much, I need more than just a small aperture to get this effect. Since I can use flash at any shutter speed, I’ll shoot at 1/2000 sec. or faster along with a small aperture to ensure I have a dark background. Try underexposing a subject 2 stops against a blue sky; the effect looks dramatic.
PUTTING IT ALL TOGETHER
When HSS was introduced, I was very excited. I found myself using four speedlights in HSS mode and adding fill-flash to mountain bikers and runners that would have been impossible before. Then HyperSync was introduced, and this technology opened up more frontiers in my photography. With my Elinchrom Rangers in HyperSync mode, I could illuminate a kayaker or fisherman in the middle of a river 60 feet away using one flash on the shore. I tried using ƒ/2.8 on my 45mm tilt-shift lens for interesting creative effects. And then I took it a step further. My AquaTech underwater housing could be used with both my camera and a PocketWizard MiniTT1 transmitter. I actually could shoot underwater High Speed Sync images! I waded out into a river with my lens half submerged underwater and photographed kayakers in rapids. Onshore my Rangers were adding fill-flash, and my shutter speed was set to 1/1000 sec. to capture the action.
No matter if you use a single speedlight or multiple large flash packs, high-speed flash photography will expand your creative possibilities. The next time you need to freeze the action with fill-flash or shoot wide open midday, use high-speed flash to solve the problem. Join the flash revolution!
Tom Bol is a freelance editorial and commercial photographer based in Colorado. To see more of his work, visit his website at www.tombolphoto.com.