Is flash sync speed important?

You're being stubborn AND you're mis-reading.

And I quote from the spec sheet on the page you sent:
"50ws - 100ws - 200ws all with 1/3000 second flash duration."

They don't get slower with the extra power pack but as you can see they certainly don't get faster.

And the nail in the coffin...the following is from the spec sheet on their signature series heads:
"Flash Duration (T.5) 1/50,000 at 3ws to 1/ 800 at 200ws"

Still care to argue?
 
You're being stubborn AND you're mis-reading.

And I quote from the spec sheet on the page you sent:
"50ws - 100ws - 200ws all with 1/3000 second flash duration."

They don't get slower with the extra power pack but as you can see they certainly don't get faster.

And the nail in the coffin...the following is from the spec sheet on their signature series heads:
"Flash Duration (T.5) 1/50,000 at 3ws to 1/ 800 at 200ws"

Still care to argue?

Actually if you just scroll down the link, the p2xx flash duration is:
50ws - 1/1000
100ws - 1/1500
200ws - 1/3000

p4xx flash duration:
100ws - 1/500
200ws - 1/1000
400ws - 1/1500

how do you argue against what's plainly printed there.

Explanation with flash duration on White Lightning and Zues flashes. The White Lightings are shorter at higher power while the pack and head system of the Zues flashes are longer at higher power.

http://www.paulcbuff.com/forums/viewtopic.php?t=59
 
Show me an AC strobe (other than the WL/AB in question) with backward specs like that and I'll bow out.
 
Er....missed the lumedyne chart then?

The lumedyne is DC. It runs on a battery.

"No HSM, Boosters, AC, or Auto"

By the way this isn't supposed to be a "real" argument. No hard feelings or anything.

I just have never seen an AC strobe perform like that. And I'm already predisposed to being weary of Paul Buff due to his "effective" junk.
 
Might I offer another interpretation of the numbers?

The only way I can see what Village Idiot (you really need a new nickname it's not helping :lol:) posted in post 32 to be right is if these were different models.

A Strobe set to output a certain luminance would indeed need a shorter duration for a higher power flash. So if you want constant lighting yes the
100ws would produce a 1/500th burst and the
200ws would produce a 1/1000th burst to keep the lighting the same.

Or am I missing the point?

Btw sorry Village you were right. I thought you were talking about the newer 1D cameras like the MkII or MkIII which are CMOS, no electronic shutter and still have 1/500th sync speeds.
 
Those numbers are typos and need to be reversed. Paul Buff has not reinvented electrical engineering. Check the specs on any other manufacturer.

Flash units that have a shorter duration for higher output are not breaking any laws of electrical engineering.

Direct control of flash duration is the simplest method for low power units - and the only one that works in auto. An auto flash must have its output controlled by controlling duration. The flash is fired from a full capacitor, then quenched when sufficient exposure has been measured. With this method you do not need to dump charge when you dial down.

That's not the only way, however. It would be entirely inappropriate for units with a large output. You can control the capacitor charge {ie the joules (J) which are the same as watt seconds (Ws)} by controlling the charging voltage and the voltage that the tube sees. This method is likely to result in a unit that has a longer duration for lower output. This is also affected by the fact that the efficiency of the tube falls as it is run at a lower voltage - ie the lumens per watt goes down, and hence the lumen seconds per watt second. Another clue is that the colour temp falls (ie a drop in the kelvin value). No rules of electrical engineering are broken. Edit: This is the cheap, easy way of doing it. No surprise?

You can also alter the capacitance.

Best,
Helen
 
Cheap? Dodgy sounds more like it. What happens if the cap is fully charged, you couldn't dial down the power without a discharge.

Garbz to model: Hold on a sec while I dial down the flash power. <Full blast of flash in her face and she runs off blind>
Garbz: Ok all se... where'd she go? :lmao:
 
Cheap? Dodgy sounds more like it. What happens if the cap is fully charged, you couldn't dial down the power without a discharge.

Garbz to model: Hold on a sec while I dial down the flash power. <Full blast of flash in her face and she runs off blind>
Garbz: Ok all se... where'd she go? :lmao:

That's what happens with a lot of studio flash systems. You have to dump the last charge when you dial down. Some units do it for you without firing the flash.

Best,
Helen
 
Really, though. I guess i"m not surprised they'd stoop so cheaply as far as engineering goes, but to the best of my knowledge they're the only manufacturer (aside from the chinese companies making OEM strobes) that builds an AC strobe like that.
 
My god! I should not be surprised, given that I've seen our own Queensland Rail switch off the thyristors which control the traction control systems by simply shorting them.

But I expected more from photography equipment which comes at such a premium anyway.
 
That's what happens with a lot of studio flash systems. You have to dump the last charge when you dial down. Some units do it for you without firing the flash.

Best,
Helen

I'm amazed that I knew you had to do that. My friend borrowed some studio strobes, and he had to flash them one last time to get any remaining charge out of them when we were done! I didn't know about anything else you were talking about, but that I did! :) *stops gloating*

BTW, from what I know about capacitors, that seems to be the case with all of them. Its not crummy engineering, its physics. Unless you put in another component that will discharge the capacitor (basically short it out in a controlled way), it will stay charged until you discharge it manually, no?


Thanks to everyone for the flash-sync answers. I found out the crazy good flash sync speed is not because the shutter is crazy fast, and I also found out a high flash sync is useful in more situations than I thought.
 
Well it's not crummy engineering it's cheap engineering. A decent way to do it would be to control duration as Helen said. But I guess that would be kind of expensive when trying to fire and release 200 joules in just a split second.
 

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