High Speed continuous flash

Hello All,

Don't know if it is possible but worth asking the experts. Is it possible to get your / any flash gun ( I have an AF 360 FGZ ) to fire continuously when you do the burst of shots ?

I was doing a birds of prey shoot yesterday and the lighting wasn't ideal and had to use as flash (with my extender) for most static shots. However, the flight was tricky when you do a burst of say 10 shots at 1/1250 F5.6 and the flash would only fire of at the first and you don't get anything. So I played around with the available light and opened up my aperture to 3.2 cranked the ISO to 800. I did get some nice shots but i think it would have been really useful if I could get the flash to fire continuously on the burst of shots.

I did notice a professional cannon user firing off the flash continuously on his bursts. Is that a cannon added feature ?

If you want continuous flash you'll need a massive energy store
HSS flash requires twice the energy for the same light as regular flash.

The Canon user was likely using a Quantum power pack (or similar) which provides the continuous 300V needed for the Xenon flash tube (rather than the usual slow charge pump from 6V up to 300V - which is what makes the high pitch whining noise )

The high end Metz flash guns have fast recharge cycle options with power packs. But in all cases you're talking about a lot of money

I can just about get the AF360 to do two flashes - but that's with higher ISO, at short range, at wide aperture (so the flash doesn't need to contribute much light).

...unfortunately it all comes down to physics
Matt

Thanks Matt. He did have a large powerpack for the flashgun. I understand its down to the flash as well for the cycle time. I will look for a compatible flash which could do that

I often suspect the battery type plays a big part too - fresh lithium or similar batteries will recharge faster than standard alkalines, giving you more flashes per minute (for want of a better way of putting it!)

If you can't justify or afford a system like the Quantum one then this might be a cheap way to upgrade what you already have. I know my local Tesco has 4-packs of Energiser Ultimate Lithium AAs for £7. Used in my K-m these gave around six months or about 600-800 images, although I've now switched to Eneloops on the grounds that they can be recharged.

Do all remote power packs/mains PSUs tend to be of the "instant 300v" type?

Matt, I use Sanyo Eneloop 2000mAh batteries freshly charged. Let me try and fond out the battery pack costs.. hmmmm

HSS isn't meant to capture fast moving objects because the flash fires multiple time so you'll see the subject move with each flash getting a bar-window effect.

Best is to use normal flash mode for this and let the flash freeze the motion.
The speed of the flash is much faster then your shutterspeed anyway.

Pentax did offer a contraption for powering motor winders from a car battery or mains supply, but I don't know if they've done anything for flashes?

Mind you, walking around with a deep cycle battery in a backpack would probably get you arrested in some places these days!

Stefan, I understand that High Speed Sync is not meant for fast moving objects the question out, of curiocity was how was the canon guy able to fire his flash on every click during a burst of 10+ shots ? and can that be done on a Pentax.

Because he didn't use HSS might be the answer
HSS most of the time drain all of the stored energy.

For example when you set the flash on 1/16th power you can surely fire it 16 times continuously.
Problem with HSS is, that it might need to fire 8 times already to cover the whole sensor for one shot so you might only be able to manage 2 photos right after each other if you're lucky.

hmm ... that something to try when i get back home. obviously i did not see what his shutter speed was... might have been 1/250th donno and might not be using HSS... thanks Stefan will try it

HSS needs to fire multiple times to cover the sensor because the shutter is infront of the sensor at the time the flash fires.
So the faster the shutter speed you use the more the flash have to fire, at 1/1250 it probably needs to fire 7 or 8 times at 1/16th instead of 1 flash at 1/16th if you used 1/180 to have the same "flash coverage".

It's true, that using fully Manual on both camera and flash will allow multiple shots.

However, the Pentax throttles down to a couple of frames per second with the AF360. Not sure what I'd get from another flash gun like the big Metz... (which can do insanely configurable multiple flashes!)

Matt

Same is true for the 540 but funny enough when i used the wireless trigger i did got the full shutterspeed.

I mostly shoot manual on cam and PTTL on flash.. will try the both manual setup.

FWIW, the Metz 50MZ5 finds it a breeze. However, the K5 slows down to about 2.5fps with flash. It's likely that if I still had the 'dumb' single-pin flash adaptor for the Metz it'd go full speed.

(The Metz was in "A" mode with the K5 in "M")

Matt