How to do High Speed Sync with Studio Strobes

For those that don’t know what maximum flash sync speed is, put a flash on your camera, in Speed or Manual mode set it to 1/400s and take a shot. You’ll see that half the frame (usually the bottom) is darker than the top.

This is where the shutter is passing the sensor too fast for the flash and it closes during the flash fire.

Up until recently, the only cameras that were capable of high-speed sync were Medium Format digital cameras (e.g. Hasselblad) that cost £10+K. Medium Format cameras have a different shutter system (usually in the lens) and so the sensor is exposed to the image in a different way.

In the older film days, 35mm cameras had a maximum sync speed of about 1/60s …. which was a bit naff.
It’s only until fairly recently the maximum you could achieve with increased to 1/250s with Nikon and 1/200s with Canon.

Although this was much improved over the old systems, it was still limiting to what you could do in broad daylight.

Then Nikon brought out what they call “Auto FP High-Speed Sync” and Canon call “High Speed Sync”.

This allows the camera to fire a speedlight multiple times as the shutter curtain passes the sensor which ‘paints’ the images onto the sensor at much faster shutter speeds.
It basically makes the flash last a bit longer so that it gets all the image lit right to the bottom

The cost for this is a bit of power.

Where your flash may be outputting F22 @1m at full power, if you increase the shutter to, say, 1/2000, you’re Aperture will need to drop to a lower value (F8?) to maintain the same exposure.

This in itself is amazing and the fact that modern strobes like the SB800 and SB900 (and Canon EX580?) can cope with this is phenomenal and opens up a lot more possibilities with your photography. It kills the batteries, but that’s why we keep spares handy

However, there are 2 drawbacks to this.
1) The camera has to be able to communicate to the flash to do this. Either in the hotshoe, using a remote hotshoe cable, or with some cameras, with the built in flash can talk to the speedlights
2) As mentioned above, there’s a power loss when increasing the sync speed beyond the native 1/250 sync as the flash has to increase it’s duration

So to increase the power you need more powerful lights than your speedlight, but you can’t make Studio Strobes sync faster than 1/250s ….. or can you ?

The answer is Yes.
Better than that, there’s 3 ways of doing it

The expensive way to do it is to use a PocketWizard MiniTT1 and FlexTT5 triggers to do this. But at approximately £225 each, its not cheap.
It will let you sync up to approx 1/500s (so I’m told) which is better, but not quite in the 1/5000s area.

In a light controlled area (e.g. a studio) use the flash to set the shutterspeed, not the camera.
The flash duration of a studio strobe varies on the make/model, but in all cases the duration is shorter(faster) at the lower power output than at full power. e.g the flash duration of an Elinchrom Ranger head can reach up to 1/6000s

This is the duration of the light emitted from the flash and in a light-tight room will be the only light source, so anything photographed will be at the flash’s duration speed rather then the one set in-camera.

To set up a high-speed shot, black out a room and set your camera to the correct ISO and f/stop for the power set on the srobes.
Set a long camera exposure (e.g. 2-20 seconds) and take a test shot with no flash.
If there’s any hint of an image then there’s ambient light from somewhere. Find it – block it.
To do the live shot you must manually trigger the strobes during the exposure …. and there you have it, high-speed sync.

The on-location way to do it is to use your existing speedlight (SB800 or SB900) to blip the light and set your studio strobe to be optically slaved and it will fire with the speedlight, but giving much more power than the speedlight could dream of.

The downside of this is that the flash needs to reach the Studio head which should be fine up to a point, but if you have remote lights beyond range or around corners, then the PocketWizards will be required

Below is a pictorial example of how to achieve High Speed Sync with just 1 speedlight and studio flashes.
NOTE: The studio lights are set to their lowest power setting throughout and my Nikon D700 is set to AutoFP on

1st shot – ambient light

I hook up an Elinchrom Skyport trigger as the BXRi has a built in receiver.

Pow!!! These things kick out some light…

Switch off the Skyport and set the camera to a ‘flash’ setting and take a shot to show that no ambient is showing

Switch the Skyport back on and … Half decent exposure. Notice the bottom edge of the frame is a bit dark. Looks like the Skyport/Elinchrom combination is not quite 1/250s which is a surprise. 1/200s will be fine though

Increase the shutter speed to 1/400 and there’s the typical sign that we’ve exceeded the sync speed

So lets try a PC Sync cable to see if that’s better

Looks fine at 1/200s. Let’s up it to 1/250s to see if we get the dark area at the base of the frame again

….. Nope – it looks fine. The wire connection is fine at 1/250s. The wireless must be a bit sluggish

Bump it to 1/400s and there’s the clipping of the frame again. Interesting that it’s much lower than using the Wireless trigger due to the immediacy of the hard wire connection

Time to try the speedlight. Ignore the settings in this picture
It was actually set to [TTL][BL][FP] for the next shots

Ambient shot at much lower settings. The speedlights pack a much lower punch so need to adjust down accordingly

Flash switched on and ….. not too bad

1/250s is showing clean edge to edge illumination

Ramped it up to 1/800 and it’s still lit fine, but notice the slight warmer colour shift

Ramp it up to 1/4000s and it’s still popping away quite happily

I now set the SB900 to manual and it’s lowest setting (1/128) as per the picture 6 up from here. It actually shows [M] [FP] to indicate that it’s in high-speed-sync mode.
The Flash hardly does anything to the image, but will easily trigger the BXRi optical slave….

Set the optical slave on and ….. hey presto. Clean image at 1/250s

Bump it up to 1/800 and, although it’s darker in the top of the frame, the bottom section is lit.

Increase to 1/2000s and it’s still lighting it. Bare n mind this is the BXRi at minimum powerand the camera settings are 2 stops darker than when using the AutoFP with the SB900

Increase the F stop to F4 rather than power up the strobe head

Hardly any change when increasing it to 1/4000s

And again virtually no change even though the camera is firing at 1/8000s
…. yes 1/8000s sync with a studio light

So there you have it. The easy way to perform maximum sync speeds on your camera and still be able to use studio lighting to light your subject.
Any comments, please add them below 🙂