Safe Flash for 20D

[tom30]

I just bought a 20D and was planning on using a sunpak 383 external flash on it. However, I have been reading that the external flash for the Canon should not exceed 6V or damage could occur to the camera. This site http://www.botzilla.com/photo/strobeVolts.html
doesn't conclude anything about the 383 but only says it is "your call." This isn't very reassuring for using the flash on my new camera.
Does anyone have any more information as to whether the 383 should or should not be used on the 20D?
Thanks.

[scottbergerphoto]

You should always use a Wein Safe Sync or similiar device between your 20D and a non Canon flash you are not sure of. I don't believe the 6volt limit applies to the 20D. If I recall correctly it's good up to 250 volts but I wouldn't try it.

[robertwgross]

It might be easier to measure the voltage if you aren't sure.

Get a DC voltmeter and set it to a scale of 300 volts DC.

Turn on the flash, and let it "wind up."

Put the meter probes carefully across the two main pins where the camera triggers the flash. Take your voltage reading.

---Bob Gross---

[tom30]

Thanks for the replies. I got a DC voltmeter and measured the voltage to be 6.8 - 6.9. Is this too high to use on the 20D?

[Andy_T]

According to this thread (http://photography-on-the.net/forum/showthread.php?t=57193&highlight=flash+voltage)250V is certainly NOT ok for the flash hotshoe.
The 20D accepts 250V over the PC terminal, but not on the flash hotshoe (still 6 V).

Best regards,
Andy

[scottbergerphoto]

According to this thread (http://photography-on-the.net/forum/showthread.php?t=57193&highlight=flash+voltage)250V is certainly NOT ok for the flash hotshoe.
The 20D accepts 250V over the PC terminal, but not on the flash hotshoe (still 6 V).

Best regards,
Andy
I read that thread and to be honest I don't see any definitive statement that the 20D hot shoe limit is 6 volts. The PC and hot shoe circuits are connected so I don't see why the limit voltage for each would be different. On page 98 of the 20D manual, Canon says:
Don't use a high voltage flash on the hot shoe. It might not work. It doesn't say it will damage the hot shoe.
I am not encouraging anyone to use a high voltage flash (greater then 6 volts) on the hot shoe without a safe sync. I am just saying that Canon's documentation on this issue stinks.

[d123]

According to Canon USA the 20D is safe on both PC and hot show socket to 250V, they actually just declared the 350D to be the same. The quote is taken from an email from Chuck Westfall and posted to another Forum.


Chuck Westfall, Director/Media & Customer Relationship, Canon USA, advises as follows regarding the flash sync circuit of the EOS Digital Rebel XT (EOS 350D):
*****

The EOS Digital Rebel XT uses a modified version of the EOS 20D's shutter unit. Consequently, acceptable trigger circuit voltage for both cameras is the same, i.e., 250 volts. Except for the original Digital Rebel, all current EOS digital SLRs (i.e., EOS-1Ds Mark II, EOS-1D Mark II, EOS 20D and EOS Digital Rebel XT) generate their X-sync signals electronically rather than mechanically. This is why they have higher acceptable trigger circuit voltage ratings than earlier models like the D30, D60, 10D and original Digital Rebel. These older models cannot be modified to achieve a higher trigger circuit voltage rating, since such a modification would require a different shutter mechanism as well as a complete redesign of the supporting circuitry.
*****

[Titus213]

That is great news. Unless of course you own a 300D.....and assuming the email is valid. Of course it's on the internet so it must be true.:lol:

[scottbergerphoto]

Thanks for the post d123. :D

[d123]

That is great news. Unless of course you own a 300D.....and assuming the email is valid. Of course it's on the internet so it must be true.:lol:

It was originally posted on DP review, by one of the more reliable posters....

Anyone wanting to see the original thread can find it here (http://forums.dpreview.com/forums/readflat.asp?forum=1031&thread=13042207)

[DocFrankenstein]

I've heard about the 6V voltage for canon so many times, I'm starting to beleive it.

And I'm using my 5.85V vivitar directly on the rebel witout much problems.

Cheers