high speed flash triggers

hi, can anyone recommend a good wireless trigger allowing upto 1/8000 sync speed off camera flash please. ?
thank you

bal

AFAIK there aren't any

High speed flash requires the flashgun to issue rapid bursts of light as the shutter curtain moves across the frame. The only way to do HSS mode wirelessly is with two AF360/AF540 combination flashguns. Mount one on the camera and use it as a master or controller (master = contributes to the lighting, controller = signalling only).

Can I ask what you're trying to accomplish?
(This may not be you, but many who ask for higher flash sync speeds ask in error )

Matt

Also, HSS is one flash mode where the shutter time value has an impact on the flash exposure .... there are separate guide number tables printed just for HSS mode taking into account each successive shorter time value. The drop off in available power is rapid. I think you would require a very powerful flash to provide much useful illumination at 1/8000th sec, unless it was extremely concentrated and directed, like with a narrow snoot.

Surely a snoot wouldn't enable a weaker flash to be used. It simply absorbs light outside the snoot circle; it doesn't concentrate it and redirect it.

G

hi matt
i basically wanted to take outdoor portraits in sunny conditions with a large aperture. wanted to mount the flashgun on a stand in a softball close to my model, therefore under exposing the harsh sunlight and achieving a shallow depth of field.
many thanks

bal

Just looking back at George's comment there , I think a snoot WILL have the effect of concentrating and directing the light ... that is what it is designed to do. So it severely reduces the angle of coverage but concentrates the light into a tighter beam which is stronger as a result. This is a similar effect to flash head zooming, but more extreme.

The practical result I believe would be an increase in effective guide number, therefore brighter light although only on a small area, say just a head and shoulders.

The OP asked about 1/8000sec .... for the AF-540 FGZ , HSS operation at 1/6000th sec , ISO 100, maximum flash head zoom position , will cause the guide number to drop to 6.2 (that's half the power of the built-in flash!). You won't light up much in bright sunlight with that unless you find a way to highly concentrate the beam ...

You can consider the use of ND filters to reduce the ambient light so the shutter speed goes to below the sync speed (1/180 on the current Pentax dSLRs).
This will also affect the flash light, so you need to adjust for that.

All the snoots I have seen are matt black on the inside. This will absorb the light that hits the inside, and the only light that comes out will be coming straight from the light source.

Unless you are making invisibilty cloaks, like Professor John Pendry at Imperial College, you will find it hard to bend light. Certainly I have never managed it.

But maybe there are better snoots that I haven't seen.

G

Don't pick a fight with the sun

Think this through...
If you intend to underexpose the harsh sunlight, then the rest of the background scene will be underexposed too. You might as well shoot at another time! (e.g. twilight or golden hour). Then you'll find that flash could be genuinely useful (though read on...)

If you are having troubles with harsh sunlight on the model, then you'll have to find a flash with at least the same intensity as the sun Rather than using flash, use a large diffuser panel above the model, and/or a reflector to fill in. Or, find a shaded area under trees, shade etc (a reflector will work wonders too)

If you insist on using flash, then you're going to need an HSS compatible flash (e.g. AF540) and a long all-pins-wired extension cable. (Wireless triggering with two Pentax flashes isn't great in strong sunlight - but then the flash doesn't really have much to add compared to the sun!)

If you don't have reflector panels to hand, experiment with white sheets of polystyrene packaging (e.g. the stuff they put around white good appliances). Diffusion panels can be done with old white sheets etc. Just improvise until you get used to balancing the light.

Worth mentioning too that moving further away from the model and using moderate telephoto will lower the depth of field for a given aperture.

Matt

The product I have in mind here is the Gary Fong Powersnoot ... A google will bring up good video demonstrations and the website for more info. Basically it has highly reflective insides which act like a projectile for the light, increasing the reflective insides which act like a projectile making an effective increase in power, much as a flash head zoom does.

This allows the flash to power through very big reductions in ambient lighting through short short shutter times, and may remove the need for complex reflectors to try and balance the sun ... You're really knocking down brightness with the shutter times, so really taking control of ambient AND flash light!

Hmmm. All the demo shots are not in "harsh sunlight" - they are on cloudy days and twilight.
Maybe it'll work for you though.

:
Believe me, having a remote flash go AWOL on a shoot is no fun, and a simple reflector is infinitely easier to set up and carry.


Always better to understand lighting principles first before plunging in with flash.
Just my opinion.

Matt

It's an idea Matt, it came to mind following what the OP was thinking about ... He mentioned 1/8000 so I imagined he was planning on knocking out a great deal of ambient light a la Gary Fong. My main point has been that to power through such short shutter speeds the flash light would need to be highly concentrated with some sort of channeling and amplifying assistance, and the powersnoot answers that need I felt .... Do you agree?

You misquoted me really, I said 'MAY remove the need for complex reflectors' .. Very unfair of you really, I am not in any way trying to contradict your suggestions which depending on the lighting and setup may be needed, with our without a snoot-type device ...I accept it all as things to consider as I hope the OP will as well. Certainly we can't provide a lighting course here, just ideas to consider.

No idea why you feel it necessary to be ' smart' and poke at me about ' understanding lighting principles' ... I don't presume about anyone's knowledge, if there's something to question or correct I do it in the interests of everyone's benefit. I have a great passion in Pentax flash, a willingness to share that and learn more ...I thought that was something we have in common and it would be great for us to build on that for everyone's benefit ....

I can't post links on my smartphone, but there is another interesting Gary Fong demonstration in Sydney Harbour in very bright sunlight where he creates an dusk effect with shutter time and the powersnoot lights the model, so I think it may be possible in such conditions. I guess it all needs plenty of experimenting though.

Interesting stuff guys.

Neil,
Apologies if it came over that way... My comment on lighting principles wasn't at you at all, not being 'smart', but a comment in general (I rewrote the reply several times, and an earlier edit made that clearer). Over the years I've often heard expresions that indicate that lighting can be somehow miraculously produced with flashguns - when mostly what was needed was some basic understanding of good lighting techniques. Saves a lot on equipment too! Frustration can run very high with flashguns - especially with everything on auto.

Going back to the OP... To achieve the snoot look you don't do that in harsh sunlight of course. That technique is definitely worth learning of course.

Rightly or wrongly, my assumption was that the OP is trying to take shallow DoF images in very sunny conditions and is looking for ways to reduce the harsh look. That's definitely a job for shade and/od a diffuser.

Hope that clarifies things - I'm not knocking anyone, just sharing 30+ years of experience

Matt

The op said he wanted HSS triggering up to 1/8000 , then he added that he wanted to underexpose the sunlight and light the model from a stand .... Any harsh ambient has been killed by the very short time value, including on the models face, so all that's left is to explore the sort of power and directional control needed for that. That was where my powersnoot idea came from.

A bit of patience and practice with it and manual mode should ensure reliability. Of course, explore all the other possibilities such as modifying the natural light with reflectors ...i guess there's loads of things to try.

My relatively short period of experience has taught me to always be open to new thinking and new ways of expressing and understanding things.