Improve Your Photography with High Speed Sync
In this article you will learn what High Speed Sync is, how it can help you become a better photographer, and how to overcome situations if you aren’t using High Speed Sync.
Strobe Photography Lesson:
Shutter Speeds, Camera Curtains, & High Speed Sync
Standard studio strobes can only deliver a full flash when the camera’s shutter speed is set below or on par with the camera’s flash sync speed – normally about 200/s. An SLR camera has two curtains that slide over the digital sensor (or film for that matter). At shutter speeds of 200/s or less, the curtains expose the sensor in its entirety, allowing a flash to completely illuminate the subject and capture the full flash on the sensor.
At shutter speeds higher than 200/s, the curtains only expose part of the sensor. As the curtains make their way down the sensor, the sensor is completely exposed to the subject before it. Because the duration of a normal studio strobes’ flash is shorter than the time it takes the curtains to make a complete pass over the sensor, the flash is only picked up by a fraction of the sensor’s coverage.
Thus, strobe photography is normally limited to exposures with a maximum shutter speed of 200/s. This limitation forces photographers to think about the following two situations:
Example 1 – Depth of Field
You just bought a super nice 50mm prime lense with a large aperture of f/1.2 to use for portrait photography. With this lens, you hope to achieve sharp detail in the eyes while delivering soft focus to the rest of the subject. Your priority for this application is to set the aperture to f/1.2, ISO at 100 and using the camera’s sync speed of 200/s. Using a strobe flash will easily overexpose your shot – even at it’s lowest power. Your ISO is already set to 100 – the lowest possible. The only way to decrease the exposure is to increase the shutter speed. Let’s increase the shutter speed to 800/s. The exposure is balanced, but now you see that there is a black shadow covering a portion of the image. This is due to the fact that at that speed, the camera’s curtains had only partially exposed the sensor for the duration of the flash.
Workarounds for example 1:
- Use a neutral density filter to stop down the exposure, allowing you to shoot within the camera’s sync speed while shooting with larger apertures.
- Settle for less depth of field – increase the f-stop.
- Shoot without a strobe under direct daylight.
- Use a strobe with HSS technology. We’ll get to that later.
Example 2 – High Speed Photography:
High speed photography is a fascinating art. High speed photography offers a way to view the rapid world around us in an instant of time. Seemingly ordinary events that unfold before our eyes in under a second are often hidden works of art that are only unveiled if captured behind the lens at high speeds.
High speed photography requires a 2000/s exposure at a minimum. Notice I used the word exposure instead of shutter speed. Since the camera’s sync speed is much slower than the required exposure time to achieve high speed stills, we are forced to shoot at around 200/s while relying on the flash to freeze the motion. The flash duration in this case must be faster than 2000/s. Additionally, the strobe’s power must be high enough to adequately provide enough power to light the subject. Examples of high speed photography might include water splashes, glass breaking, and anything that explodes. View examples of high speed photography.
Workarounds for Example 2:
- Shoot within the camera’s sync speed while relying on the strobe to freeze the subject using a flash duration of at least 2000/s.
- Shoot without a strobe under direct daylight.
- Use a strobe with HSS technology.
High Speed Sync to the Rescue!
Strobes and flashes equipped with High Speed Sync (HSS) overcome the speed sync limitation by emitting a series of smaller-powered flashes that let light through the partially opened curtains as they completely expose sensor. Most units with HSS allow shutter speeds up to 8000/s – high enough to achieve the needs of most photographers. Those that require shutter speeds higher than 8000/s are likely tasked with conducting science experiments.
How to Set Your Camera for HSS Use
By default, your camera may not allow you to shoot at a shutter speed higher than your camera’s sync speed. The instructions below are for setting HSS on the Canon 6D. Other Canon cameras may have similar settings. If these settings are not available in your camera, consult your trusty camera manual.
- In your menu settings, select External Speedlight control
- Select Flash function settings
- Change ETTL to “M” (for manual) – Notice the flash icon with the “H” below the big M letter indicating that the camera is ready for High Speed Sync.
- Change the shutter speed above 200/s
Downsides of High Speed Sync
As with everything in the world of photography, High Speed Sync is not without compensation. There are two major drawbacks to using High Speed Sync:
- Power – With HSS, the strobe’s power output will be less than those with non-hss flashes. Because HSS uses a burst of multiple flashes, each exposure requires more power.
- Flash duration – The extra pulses created by HHS will result in slightly longer flash durations. With certain HSS strobes, this is barely noticeable.
- Price – Strobes and flashes with HSS technology are about double the price of those without.
What HSS Strobe Should I Buy?
While there are many HSS studio strobes out there and there are use cases for each photographer, I suggest taking a look at the Godox AD600BM. I’ve used it for just a while now and absolutely love it. It is priced much lower than comparable products and meets just about all of my requirements of what a monolight should provide. The only downside is that this thing is heavy – so be sure to use high strength light stands or optionally use the AD600 Handheld Extension.
Note: I am not paid to promote Godox products. Just a happy customer.
Graham Houghton provides a thorough and accurate review of the Godox AD600 in the video below.
High Speed Sync is a wonderful technology that allows photographers to easily freeze motion and capture subjects with large apertures while providing quality lighting that strobes, flashes, and monolights provide. If your budget allows you to upgrade your existing strobe(s), HSS will allow you to offer a higher spectrum of photography solutions while increasing the quality of your images. Happy shooting!
Thanks to u/SteveAM1 for contributing to this article!