Off camera flash..help

Hi everybody

This may be a stupid question but a bit new to this side off things.. 99% of my photography is motocross, so a mixture of high & low shutter speeds. With winter approaching & all those really gloomy days coming soon in the uk, I thought i'd have a play with setting up some flashes on my favourite jumps off camera to see what I can capture.

I would like to set up two flashes off camera, distance would be up to about 20 metres between flashes & camera. I have two 580ex's

I have read so many articles on here now i'm confused....

What would be the best set up? what transmitters? I use high shutter speeds at times so high sync would be needed?

Any advice would be a great help.. thanks

old git wrote in post #8550744
Hi everybody

This may be a stupid question but a bit new to this side off things.. 99% of my photography is motocross, so a mixture of high & low shutter speeds. With winter approaching & all those really gloomy days coming soon in the uk, I thought i'd have a play with setting up some flashes on my favourite jumps off camera to see what I can capture.

I would like to set up two flashes off camera, distance would be up to about 20 metres between flashes & camera. I have two 580ex's

I have read so many articles on here now i'm confused....

What would be the best set up? what transmitters? I use high shutter speeds at times so high sync would be needed?

Any advice would be a great help.. thanks

You are caught in the middle of a conundrum. As you know, there are two ways to stop motion, fast shutter speed, or by freezing the action with flash. If you add flash to a fast shutter using HSS you lose a ton of power so the effective range of your flash is very diminished. I dont know how fast a shutter speed you need for motorsports but I would imagine it to be higher than 1/1000. Also when you go into hss mode, the flash doesnt aid in freezing motion as it becomes a series of pulses rather than one flash. Getting your flash off camera and retaining ettl is pretty expensive as well.


You can use the short duration of the flash to freeze motion, but the ambient light has to be low enough that it doesnt contribute to the exposure and cause blurring. If you shoot at 1/250 with daylight you are going to get some motion blur in addition to the action stopping flash burst.

Your best and cheapest option might be to try shooting in low light/night shots. You could rely on the motion stopping ability of the the flash rather than the shutter speed. Cheap radio triggers will suffice for this sort of work but in low light the canon wireless system will work.

You can't have high speed sync with standard radio slaves, RadioPoppers do it but you lose a lot of light. I suggest shooting at the cameras sync speed, or as fast as the radio system can keep up.

I recommend Skyports, extra receivers here. B&H delivery to the UK, you might get charged import duty/tax, or you might find them locally.

Thanks Guys. Any advice is good.

Most of my shooting is well above 1/1000, do some motion down to 1/125. But the flashes are mainly for the higher speed stuff. Have just ordered some cheap radio triggers, but in time would like to end up using a system using ETTL, the budget isn't a problem.

So will the Pocket wizards cope with the hss? I take it, the triggers I have ordered will cope with hss?? CTR's

Will have a look at the skyports, radio poppers are out, seems to be no way of getting them in the uk.

Any other suggestions welcome...

HSS is part of ETTL, so no, they won't. You can't shoot any slave flash and get full power at 1/1000th. Only radio poppers will even give you hss, I see them as a bit of a cludge though, and the new PWs aren't recommended yet.

The point of flash is it freezes motion, you set your exposure so it drops ambient light to the left you want then the flash lights the subject.

The new PW system will acommodate ettl, and HSS from what I understand, I have no first hand experience with it though. Lots of users are complaining that the canon flash systems have limited range with then due to RF interference though. If you went with the CTR's you may find that your sync speed is less than the full 1/250 that you camera is capable of.