563optimized_hss_caption_cropped_resized.jpgMore Power:  2-4x increase in power

More Battery:  2-4x increase in battery life

Faster Recycling: 2-4x faster recycle speed



High Speed Sync is a great feature found on Canon flashes, but it has its limitations.  By pulsing light over a period of time, you can effectively get rid of sync speed limitations.  This uses more power then a normal flash pop but the ability to use any shutter speed generally overshadows this problem.

The real challenge with HSS is the need to have the flash close to your subject, as the pulsed light is not as bright as a regular flash pop.  Since HSS is a great feature to use in bright sun situations, a challenge arrives when you want to place your flashes close to your subject and use the built-in infrared trigger system – infrared will not work well in bright sun situations.  Then there is the issue of power consumption using HSS.  Enter PocketWizard.  We’ve taken Canon’s great feature and made is better, stronger, and faster. 

ISO 100 // f 2.8 // 1/6400 sec.
First, by using radio instead of infrared you can trigger your remote flashes outdoors, in bright sun and at distances far greater then infrared will allow.  Now you can place your flashes close to your subject and step back to use a longer lens.  When any shutter speed can be used, you can open up your aperture all the way to soften your background or just use a high shutter speed to knock down the level of ambient light.  This is a great way to get fantastic photos in the middle of the day in harsh sun.

But HSS is a battery hog as it needs a lot of power to pulse the light.  Through extensive experimentation, we found a way to reduce the total power used while giving you more power, and thus more light, when you need it. This means more light (which equals greater working distance), faster recycling times and more flashes per battery set when shooting in Canon's HSS/FP Flash mode.

Because the MiniTT1 Transmitter and FlexTT5 Transceiver communicate through-the-shoe with the camera system, they can control the HSS burst duration.  By precisely matching flash duration to the shutter speed, large gains in efficiency are found, as much as 70% in many cases, for both remote and on-camera flashes.

This gain in efficiency is immediately translated into shorter recycle times (allowing faster HSS shooting), and more shots per battery set.   Additionally, the efficiency gain means there is more power available when needed, up to two stops more, thus allowing photographers to place flashes farther away from their subjects or smaller apertures when using HSS.

ISO 100 // f 2.8 // 1/5000 sec. 12 Noon
When shooting in E-TTL, the camera determines how much light is needed for a given shooting situation and makes a request to the flash for that amount of light.  If the flashes are within a proper working range, they fire the needed amount of light and all is good.  However, if the lights are too far from the subject, they will fire but the shot will be underexposed.  Now with optimized HSS, the flashes have more power available and the maximum brightness is greater allowing the working distance between the flash and the subject to be extended before you reach a point where the shot will be underexposed.  You can now simply use a smaller aperture if desired.

In manual mode, this gain in efficiency is translated into a brighter burst at the various power settings, as much as two stops brighter.  It can do this because there is more power to use since it is not being used for a longer duration pulse.  This will allow you to either use a lower power setting or a smaller aperture, depending on your need.

You can also now disable HyperSync™ mode in the MiniTT1 and FlexTT5, allowing use of HSS for shutter speeds down to 1/320 second. This is especially useful for the Canon 5D and 5D MK II whose shutter mechanisms can’t take full advantage of the HyperSync mode. 

It’s worth noting here that HyperSync is actually more efficient then HSS flash so if you are using shutter speeds of 1/500 or less, HyperSync might be the better option.  The new firmware allows you to set the crossover point at which the system switches from HyperSync to Optimized HSS Sync.

The following snapshots from our lab equipment show a more precise view of what’s going on:


-    The purple line at the top is the normal sync pulse from the camera.
-    The fuschia line is the flash duration during HSS (with a few variations
     at different shutter speeds).  Flash duration is much longer to allow it
     to sync with the faster shutter speeds.
-    The green line is when the shutter starts opening.
-    The gray line is what a normal flash burst would be.

Graph 1 shows HSS Mode without the addition of the ControlTL firmware.

(Graph 1) Normal HSS














Graph 2 shows HSS Mode with the new ControlTL Firmware v4.250 in the MiniTT1 Transmitter and FlexTT5 Transceiver.
-    Note the difference in total flash duration as it matches precisely to the shutter speed. 

(Graph 2) Optimized HSS with new ControlTL Firmware 4.250














Graph 3 shows max power output gains in manual mode.

- The light gray line is the HSS flash burst when used in MANUAL mode. Because the flash duration has been optimized, there is more power available to the flash during manual 1/1 flash resulting in a brighter flash burst.

(Graph 3) Max Power Output




Use FP Sync to control ambient light while shooting in bright conditions. By allowing you to use your camera's high shutter speeds, you can knock back the ambient light and still use a wide aperture to soften backgrounds. When you underexpose the ambient light with flash, you get some very interesting results.

Combine these features with up to eight frames per second (8 fps) shooting speed and you have truly unmatched capabilities.  Even if you don’t want TTL, you will want the new MiniTT1 on your camera.

Once again, Rob Galbraith has done a great job explaining the tech on his blog here.