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BYork
12th of February 2005 (Sat), 18:05
Do you have to use the Canon flashes for the 20D? I was told if you used a different brand it would ruin the camera...this was told to me by Wolf Camera and Video where I purchased the 20D.

Thanks in advance!

Citizensmith
12th of February 2005 (Sat), 21:04
Most modern flashes will work fine with the 20D, although the Canons may offer a few features you won't find elsewhere. The only thing to watch is the trigger voltage of the flash. The 20D has a low trigger voltage and using a flash with a high trigger voltage (older or studio flashes for example) can damage the camera.

HJMinard
12th of February 2005 (Sat), 21:11
Try not to listen to Wolf Camera salespeople ... much of what they say, including this, is hogwash. There are many non-Canon - yet compatible with Canon - flashes that will work just fine on the 20D. Sigma and Metz are two of the more prominent alternative brands.

FlipsidE
12th of February 2005 (Sat), 21:33
I heard something like the following from a wise man, "Wolf Camera is just a corner drug store photo lab that happens to sell photography equipment." I cannot stand them. Unfortunately, they are really the only worthwhile camera store in town. There is one other in my city, but I wasn't terribly impressed when I went in to look around. I've heard there's another about 30 miles from where I live that's actually really impressive. But, I haven't been that way yet.

I say all that to say this...I have only one worthwhile camera store/chain in my city...Wolf Camera. And, after the experiences I've had there in the past as well as what I've heard on these boards, I refuse to go there anymore...not even to look around. I do all my shopping online and get all my advice from these boards.

I can't recommend the above advice enough. Stay far far away from Wolf Camera.

To answer your main question, though...unfortunately, I don't know enough about non-Canon flashes to be able to tell you. Though, I would recommend the 420EX or 580EX from Canon. Both seem to be highly recommended here.

FlipsidE

Jim_T
12th of February 2005 (Sat), 21:52
Some older flashes can have over 100 Volts on the pins.. You risk camera damage using one of these. You only want to see about 5 volts. If you're going to get a non-Canon flash, that's something to look for. As Citzensmith says.. Usually the older flashes have the high voltages.

Also you should select a flash that supports what's called 'E-TTL' (Evaluative - Through The Lens metering).

This mode meters through the use of a pre-flash. The 20D is an E-TTL camera. When you take a flash shot, there are two flashes.. They're so close together you can't easily tell there were two of them. The light reflected from the first flash is evaluated by the camera and in a tiny fraction of a second, the camera determines the flash power to expose the scene correctly then fires the main flash at this level.

All the Canon flashes with the EX designation do this. (ie 420EX, 580EX etc)

E-TTL is fairly new.. Most Canon compatible flashes are just TTL... TTL lenses will work, but they can't do the evaluative pre-flash.., Without the ability to evaluate a pre-flash, the camera will always fire at full power This requires that you to manually adust the exposure by setting the aperture or shutter speed as conditions change.

Monito
13th of February 2005 (Sun), 03:37
Photo Strobe Trigger Voltages: http://www.botzilla.com/photo/strobeVolts.html

Arsonist lolol
13th of February 2005 (Sun), 04:00
I can't help with the flash question, but just wanted to say thanks to Jim_T for his post, that cleared a lot of things up about flashes, so...thanks lol! :)

Bruce Watson
13th of February 2005 (Sun), 05:31
Per Jim's reply, only the Canon EX or a few other compatible 3rd party brands will work with the full automation functions of your camera.

The only ones I am aware of are the EX series of Canon and the Sigma 500 Super DG.

If you buy other brands there is the risk of too high voltage as mentioned and it will not integrate with the E-TTL automation.

There is an EOS flash sticky in this forum, you should have a look at it.

The sales person at Wolf was not necessarily lying to you, but maybe could have give a few more details in the explanation.