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|| SportsShooter.com: Member Message Board
Yes, your 580exII is defective...
Tim Snow, Photographer
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Montreal | Qc | Canada | Posted: 11:30 PM on 02.16.11 |
->> Amid all of the controversy concerning 580exII's getting fried when used with Pocket Wizard Mini's and Flex's, it turns out to be a Canon design fault. I will not try to paraphrase what Pocket Wizard found in their research (maybe someone not as tired as I am will be able to...) but here is the link to the study LPA design performed...
http://lpadesign.com/580EXII.pdf
So, yes, the problem lies in the Canon design, and no, using Pocket Wizards won't destroy your flash. |
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Tim Snow, Photographer
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Montreal | Qc | Canada | Posted: 11:38 PM on 02.16.11 |
->> "So while PocketWizard products do not appear to cause the failure, through aggressive marketing of
remote HSS features of Canon’s flashes we may be accidentally contributing to the rate in which failures
happen."
Meant to include that quote in the above post. |
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Neil Turner, Photographer
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Bournemouth | UK | United Kingdom | Posted: 5:47 AM on 02.17.11 |
->> The truth is that speedlights (Canon or Nikon) were never designed to be constantly fired over extended periods at, or near, maximum output using high capacity NiCd or NiMh batteries. A large number of the users of these new Pocket Wizards are trying to get the performance of location lighting systems from kit that just is not 'man enough'.
Frying flash tubes or other components is nothing new. I remember destroying a number of SB25 and SB26 units when using Quantum Turbos in the early 1990s.
I never drive a car at, or near, it's capacity for extended periods. They aren't designed to do it and neither are speedlights. |
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Kevin Krows, Photographer
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Forsyth | IL | USA | Posted: 6:57 AM on 02.17.11 |
| ->> I'll stop using them now. Joe McNally and David Hobby should do the same. |
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Andrew Scott, Photo Editor, Photographer
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McLean | VA | United States | Posted: 8:37 AM on 02.17.11 |
->> Neil,
Read the white paper completely. It is long and highly technical, but the conclusions are exactly the opposite of what you are saying.
The failures are NOT happening due to repeated firing at maximum output, but rather the cumulative effects of short, small bursts in High Speed Sync mode of Canon's own design, misaligned flash tubes, and ozone buildup within a sealed flash head that is causing arcing which ultimately leads to failure of a IGBT resistor in the 580EX II. Repeated full power dumps are not raising ozone levels in the flash head to levels that appear to be the trigger for electrical arcing that leads to failure of the IGBT resistor.
According to LPA, this issue is only related to the 580EX II, not the original 580EX, nor the 430EXII.
LPA should be commended for doing such a thorough piece of research engineering.
Your point about overdriving Speedlights is right in theory, but is probably only applicable to older units. Years ago I've burned up several 283/285's hooked up to Jackrabbit packs when lighting high school basketball. But most all of the modern Speedlights from Canon or Nikon now have thermal overload protection and should shut themselves down before you get to the meltdown point. |
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Neil Turner, Photographer
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Bournemouth | UK | United Kingdom | Posted: 11:36 AM on 02.17.11 |
->> Kevin - Just because some photographers do great work using the kit in ways it wasn't designed for doesn't mean that when the kit fails it is necessarily due to poor design or manufacture.
Andrew - I did read it all of the way through and they have done a lot of testing of their own theory but have not gone very far to see if there is an alternative explanation. We all know that flash units get overheated and 99% of the time it is because they have been pushed way too hard. The high speed synch theory is an interesting one but I haven't heard of any failures of Canon speedlights regularly used on high speed synch without the Pocket Wizards.
I'm not saying that the 580exII doesn't have a design flaw, all I am saying is that the units were not designed for the use they are now getting. |
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Israel Shirk, Photographer, Assistant
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Boise | ID | US | Posted: 5:16 PM on 02.17.11 |
->> Neil- It really sounds like you just didn't even read the article and are assuming you know what it says. It says the opposite.
Quick summary of the paper:
Heat is not the main factor which is causing these heads to fail. It's generation of ozone inside the flash head, which leads to arcing from the flash tube to the reflector and also results in failure of the IGBT circuit. It is unclear from the paper whether the ozone itself causes the IGBT failure or whether its contribution to arcing causes increased arcing.
I would venture to guess that slight amounts of arcing initially present results in the ozone gas, resulting in a decrease in the breakdown voltage of the gases inside the head. As the breakdown voltage continues to decrease, the head arcs more. The arcs are likely jumping across the gap to the reflector because of improper grounding - which results in the voltage being fed into a part of the IGBT which is unable to handle it.
It also follows from the use of the IGBT initially that the arcing will take place at any flash power. IGBT's just cut off the end of the discharge from the capacitors; they do not decrease the voltage which is in use. Thus the duration of the flash changes when the flash is powered up higher, not the voltage across the flash tube. All that is necessary to cause the observed issues is arcing, which comes from too high a voltage for the conditions.
Regardless, when the IGBT circuit fails, the flash head can then no longer fire at less than full power. The IGBT usually serves to restrict output when firing preflashes, HSS flashes, and lower-power flashes. Its failure causes the flash to completely discharge on any kind of flash.
On page 17 it's detail how Canon used a slightly better head design on the 430EX II's - it allows for venting of ozone, a different mounting mechanism, and a different coating for the trigger wire. Most significantly, it has a much larger gap between the flash tube and the reflector, which would require several times as much voltage to arc.
Also, it is important to note that the use of FlexTT5's actually DECREASES the amount of ozone generated! This is shown in figures 15 and 16.
So, in conclusion, yes, it's a Canon problem, and they solved in the 430EX II. Using FlexTT5's over optical sync will decrease the probability of you having this problem.
Moral of the story: Use 430EX II's for slaves. |
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Neil Turner, Photographer
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Bournemouth | UK | United Kingdom | Posted: 5:38 PM on 02.17.11 |
->> Dear Israel
Congratulations your knowledge of the research is more through than mine. Is that what you want to hear? I did read the document. I happily acknowledge that the theory that it supports might be right but IF you bothered to read what I said you wouldn't have bothered to precis it.
With nearly 25 years in the business, I like to think that I know a thing or two about shooting flash with all sorts of kit and one of the things that I have learned is that kit fails when you ask it to do more than it was designed to.
I'm really not trying to start a fight here - but surely you must acknowledge that LPA have quite a lot riding on it not being their fault. I'm sure that Canon, for their part, will make sure that the mark three will be designed so that a third party accessory cannot inadvertently contribute to it's destruction.
For the record I own hundreds of pounds worth of LPA kit and I would credit the Pocket Wizard as being a piece of equipment that literally changed my working life.
Moral of the story? Don't bother sharing your thoughts. |
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Sam Morris, Photographer
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Henderson (Las Vegas) | NV | USA | Posted: 6:02 PM on 02.17.11 |
->> "Moral of the story? Don't bother sharing your thoughts."
And people wonder why Joe Cavaretta decided not to renew his subscription. |
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Kevin Krows, Photographer
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Forsyth | IL | USA | Posted: 7:26 PM on 02.17.11 |
->> "it wasn't designed for"
Why does the 580EXII have a sync port? Why does Canon include a cold shoe stand with a 1/4-20 socket in the bottom with all their flashes? Why is there Master and Slave modes? Why are there slave groups A-B-C. Why does Canon make the STE2? Why does the STE2 allow A-B Ratios.
What do you mean ... "it wasn't designed for"? I'm not following your logic. |
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Israel Shirk, Photographer, Assistant
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Boise | ID | US | Posted: 7:34 PM on 02.17.11 |
->> Neil-
I was summarizing the article so that other people don't have to read the whole thing. I'm not trying to shove anything down your throat. I apologize if it came across that way.
The reason I'm not sure if you read or understood the article is that it appears from your posts above that you think it's from using them too much at a high power or in another situation which would normally harm them. The article is clarifying a problem that some people thought was coming from using flextt5's with 580's, resulting in the flash suddenly firing only at full power. |
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Neil Turner, Photographer
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Bournemouth | UK | United Kingdom | Posted: 2:25 PM on 02.18.11 |
->> Sam - totally agree. Renew subscription? Probably not! Sports Shooter has been a very interesting forum but the viciousness of some responses takes your breath away.
Israel - I still think that there are other possible causes of the failure that haven't been properly addressed by LPA. Their theory fits, but so do several others. Being around other photographers as much as most of us are I tend to believe that very heavy duty use with external batteries or Nickel Zinc AAs is every bit as likely to be the cause - something that anyone hoping to get a free repair would never own up to. The other point is that the way high speed synch works means that the flash is very often working at, or near capacity - even if it isn't being asked to work at small apertures. Try shooting a subject ten feet away at f4 on 200 ISO with a shutter speed between 1/500th and 1/2000th and then tell me that the unit isn't using a lot of juice.
Kevin - wow... to take your points as one... if any or all of the other Canon products caused a Canon flash unit to fail then it is, without doubt, a Canon issue. This piece of Pocket Wizard kit came onto the market after Canon designed, tested and launched the 580exII. If there have been countless failures when the two items are used together then you have to wonder. Don't you? What on earth has the existence of a synch socket, a plastic shoe and the ST-E2 got to do with this conversation? Is it me that you have the beef with?
The Canon 580exII was designed to be used off-camera - that is why they have these other accessories and ports. If it can be successfully used with third party products without being damaged, all well and good. You cannot call a piece of kit that seems to me to function perfectly adequately when used with the accessories it was designed for "faulty".
Feel free to come back and argue... I promise to let you have the last word. |
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Kevin Krows, Photographer
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Forsyth | IL | USA | Posted: 5:49 PM on 02.18.11 |
->> Neil - Please be assured that I do not have any issue with you personally. I have all the respect in the world for your experience and your opinions based on your personal use of lighting equipment.
My position -- Canon speedlights an Control TL are man enough and they are designed for off camera use. I've been a beta tester for over a year for LPA/PW, have used their TT1/TT5 extensively in my work. I also use studio lights but have found myself using speedlights more and more for location work.
I had two 580EXII's go bad at the same time. I was testing the soft shield when they blew. Sent the flashes to Canon for repair, stopped using the shields, and "all is well and good." If I'm within 25-30 of my lights I use my 580EXII's. For setups greater than that, I use the 430EXII's. That's how I get around distance issues.
I haven't had any performance issues since then and love pushing this kit to the limit. |
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