Yongnuo Flashes and triggers with High Speed Sync or HSS

High Speed Sync flash is your DSLR’s ability to use a flash at shutter speeds faster than the camera’s native sync. Most cameras have a native sync of 1/250th of a second or less (for example Canon 6D has 1/180 sync speed which is very slow), and anything faster than that is beyond the camera’s ability to sync the shutter with the flash. But if you happen to be in a situation that requires faster shutter speeds to effectively capture the action, or for other aesthetic reasons (like a wide aperture), then you’ll over-exposure your image. However, high-speed sync flash/camera combinations allow you to use the flash at higher shutter speeds.

There are many positives to working in HSS, the first of which is being able to control the ambient light and shoot at a shallow depth of field. It is a very liberating experience to shoot HSS and not having to worry about flash sync limitations, or the time of day. I feel like most photographers don’t want to have limitations when they are spending a lot of money on cameras and lights.
Obviously you can guess that the biggest and possibly only drawback to using HSS is the power drop-off at higher shutter speeds. If you are doing senior portraits, headshots, environmental shots, weddings, or things like that outside, you may have to run your speedlights at full power a lot more often, or combine speedlights in a single modifier, but generally it isn’t that big of deal. For some shooting situations you may also still have limits to the time of day.

Most recent models like Yongnuo YN600EX-RT, Yongnuo YN568EX II, YN568EX, Yongnuo YN685, Yongnuo YN500EX support High Speed Sync. You just need to select HSS mode on the speedlite or through camera flash menu to be able to use fast shutter speeds. Also, if you are interested in off-camera lightning you will need HSS enabled radio triggers like Yongnuo YN622C for Canon or Yongnuo YN622N for Nikon, or Yongnuo YN-E3-RT if you are into Canon new RT system.