Is It Safe Using Sunpak Auto 611 Flash with a 20D?

Hello,
I have a Powerful grip flash, the Sunpak Auto 611, which I would like to use with my 20D body. My research indicates a distinct voltage danger when many old flashes are synched via the PC socket, but this flash synches on the HOT SHOE via a corded 'Auto Sensor Module'. I am not finding any information about issues to watch out for regarding 'Old Flashes' on Hot Shoes and EOS cameras.
I don't have a decent backup to my 20D at the moment otherwise I'd just slap the flash on and TRY it. I seem to recall successfully shooting a lot of images with the Sunpak on my DCS-520 (An EOS-1n to dSLR Conversion by Kodak). This was a few years ago. Would experiments with this camera extrapolate to my 20D on a reasonable basis?
I definitely and distinctly want to be shooting with a modern 'EX' flash and not an Antique! But earning the money to buy one would be exceptionally easier if I can lean on this Powerful work horse for the moment.

Thanks All

Richard in Michigan

I can say for sure the older 10d had mechanical contacts that could be overloaded by something like the Sunpak.

Somehow, I came to believe that one of the improvements of the 20d was the optical triggering - which was voltage/current insensitive. I have absolutely no proof or documentation - so I guess you are about where you started.

Now that I think of it, it may have been in the 580ex flash manual...

According to this page http://www.botzilla.co​m/photo/strobeVolts.ht​ml

Here http://www.bobatkins.c​om …raphy/digital/e​os20d.html it says

The 20D should be safe up to 250V (see here). The question is what is the trigger voltage for the Sunpak Auto 611. Have you measured it?

e-k

Original Poster Here:

Two Things

a) I had a 'Homer' DOH! moment. ie: Pickup the PHONE! I went to the ToCad (Sunpak) website, got their phone number and asked them Directly. I took the Tech Support option from their voicemailhellsystem and the 'tech' answered my question about an Auto 611 on an EOS 20D with an immediate "NO - the voltage is to high."
-- Unfortunately, this 'Clear' answer was seriously Muddied up by later clicking on an above posters link to an article by Chuck Westfall (A long time Official Canon Rep.) As part of the Q&A he responded to a flash triggering voltage inquiry and to summarize said an 'Official' Canon Voltage Limit List won't happen, but he has a 'Personal' one to share. 'B' is the quote from his article.
b)
I recently posted a question regarding the safe maximum sync voltage for an EOS 30D on http://www.openphotogr​aphyforums.com/. A reply led me to an article called Tech Tips answering a number of Canon-related FAQ. You addressed the safe sync voltage for a number of models, including the 20D, but I was wondering where I might be able to find published data on the safe sync voltages for the entire range of Canon cameras (or maybe just the 30D, as that's the body I'm using now).

It's likely you'll never see an official list of all Canon SLRs according to this specification, because Canon Inc. (our parent company in Japan) simply doesn't do things like that. I've been with Canon USA since 1982, so I'm in a pretty good position to know Canon Inc.'s habits. However, I'll be happy to provide you with my unofficial list:

Canon Digital SLRs safe for TCV up to 250 volts:
EOS-1D Mark II N, EOS-1D Mark II, EOS-1Ds Mark II, EOS-1D, EOS-1Ds
EOS 30D, 20D, 5D
EOS Digital Rebel XTi, XT (400D/350D)
EOS D6000/D2000, Kodak DCS560/DCS520 (circa 1998)
EOS-DCS series (circa 1995)

Canon Digital SLRs safe for TCV up to 6 volts:
EOS 10D, D60, D30
EOS Digital Rebel (300D)

Canon 35mm SLRs safe for TCV up to 250 volts:
EOS-1V, EOS-1N, EOS-1, EOS 3

Canon 35mm and IX240 SLRs safe for TCV up to 6 volts:
EOS 650, 620, 630, RT
EOS 850, 750, 700
EOS Rebel Series
EOS Elan Series
EOS 10s, A2E, A2
EOS IX, IX Lite
T90

Canon SLRs released earlier than the T90 did not have TTL flash circuits, and comprehensive information on safe TCV levels is not available.

The trigger circuit voltage (TCV) rating for any EOS SLR is the same on the hot shoe as it is on the PC terminal (if the camera has one), but the acceptable TCV level varies according to the camera model. Incidentally, the main reason for the difference is the way the X-sync signal is generated. With the 250V cameras, the X-sync signal is generated electronically. With the 6V cameras, the X-sync signal is generated mechanically. There are no guarantees, but going forward I anticipate that most if not all future EOS SLRs will be safe for TCV up to 250 volts.
--Whew, a comprehensive answer that 'feels' definitive ---

c) The Sync Voltage for Sunpak 611's is listed at 190v at the places I've seen Online. How do I test the voltage of my particular unit? I do have access to a nice Electrician's Meter? (I don't know what it's called), but the person who knows how to use it is 1200miles away for the next couple of weeks.

Thanks All for your Inputs.

Richard

Use the meter to short the big center contact on the flashes shoe with its side (in the mounting groove) contact. More details on a link from this page.

Way to go jeongyun, E-K, Zeissfan, and Jon. I like the unofficial list from Mr. Westfall - That man is TOP NOTCH!

Jon - I think using a meter to short the flash circuit may not work - the trigger time might be too short to catch on a "normal" meter - you may have to resort to a quick response max holding type meter, or an oscilloscope. But he could go to that nice link you sent and match model numbers up...

I think there may be something that can be put in series with the sync cord that will keep the high voltage in a circuit out of the camera, and produce a low voltage/current trigger the camera can handle. You may want to check one of the lighting speciality type sites, or one of those external power pack type sites.

Original Poster Here:

a) Wonderful & Constructive Replies Have Been Posted - I'm very grateful everyone.

b) I went to the 'family' workshop and retrieved an $Expensive$ Multimeter and with a little trial and error sniffed out how to use it. It kept saying OL (for overload) until I found the 'step' button to ramp the sensitivity down from ".xxx" volts to "xxx." volts. I know from conversations with my Dad that it's takes a pretty big OOPS to ruin one of these (They're surplused from his employer only because you can't operate it with the fireproof gloves their safety plan mandates around electricals at the meter's maximum capacity) Using semi-strong alkaline C cells, it takes four of em, it wandered around the 140-150v area at most. As someone noted - when properly set - the Multimeter didn't fire the flash. I don't know if the actual flash tripping point would give a different voltage. I'm not an Electrical Tech Head - I'm a "Photo Geek" with Strong Macintosh Tendencies .
c) I am going to track more of the Links people have posted to this point, but I now have much more confidence in the likely hood that this particular flash won't be 'Ruinous' on a 20D because I checked & YES! I did use this flash with my Kodak DCS-520(EOS1n Modified to 2mp Digital) with nice results. Further, the 1n, the dcs520, & the 20D are listed as 250v safe in Mr Westfall's listings.
d) This is quite a relief to be able to, probably, use this Monster flash. I have the opportunity to do some small weddings here locally and the 611 Sunpak is the only Powerful flash available to me until I actually DO some jobs and start buying equipment.

I'll post more asap

I have the same flash and want to try it on my 30D...

So....how did it work on your 20D????

Thanx...