20D: Seeing but not Synching with 550 or 420 flash

[NJMurphy]

So I'm sitting in the car this morning, waiting for a realtor (who is late as always) so I can shoot the interiors of the house she's listing. I have the 20D with the grip, 17-85 EF-S and a 550EX flash.

I slide the flash into the shoe, tighten the wheel, and move the switch. It whines, and the pilot light glows red.

The camera turns on next. An empty 1 GB card in place, I check the viewfinder.

Hmmm..no lightening bolt. I press the shutter. Exposure, no flash. I twirl the zoom. The flash head is moving; I can hear it. The focal length numbers change on the display, but that's as far as the units go in talking to each other.

Same results with my back-up 420EX. Zoom registers, but no synch, no ready symbol.

(I wound up shooting the job with my back-up Drebel, BTW.)

I've been shooting sports with the camera all week, lacrosse, softball and baseball, with the 100-400L with no problems. (And without the flash.) The only thing I've done out of the ordinary recently was synching my studio lights with the PC outlet.

So I'm stumped. Has this happened to you? Anyone have any ideas? Or will I wind up schlepping down the Jersey Turnpike Monday morning?

[Doug_Kerr]

Hi, Murph,

Any chance you have inadvertently set camera C.Fn-07=1? That prevents the flash from firing, and in that state, it does not report "ready" (thoughtful, no?). But all the head shifting for focal length still happens.

Otherwise, I would suggest "rebooting" the camera - take out the main battery for a little while and then start up again.

It may be that the firmware just got baffled somehow (the formal technical term is "brain fart").

[NJMurphy]

Thanks for the quick reply, Doug. I should have noted that I tried removing the main battery already, I did that when I got home, and before posting my query. (I don't ask for help much, and I didn't want this to wind up as being as easy as a reboot.)

I'm going to try taking it out again for an hour or so. As for C.Fn-07, I don't think I'd have done anything with that, but pulling the main reset all the CF's, and it still didn't work.

I hope it's simple; I've got several games next week, fortunately all outdoors, so if the camera needs to be left I'll have to wait on the repair till I can spare it for a week...

[Doug_Kerr]

Hi, Murphy,

Pulling the main battery certainly doesn't reset all the CF's. (We'd all be way irritated if it did!)

Best regards,

Doug

[Jack_Kurtz]

I had a similar problem with my D30 3 or 4 yrs ago. It had to go back to Canon for repair. jack

[Jim_Larson]

The other possibility is that the contacts (on the camera -> since it happens with two different flash units) need to be cleaned. Try that first. .. then send for service.

BTW: Kudos on having a backup!

[Dennis_Wood]

[ QUOTE ]


I've been shooting sports with the camera all week, lacrosse, softball and baseball, with the 100-400L with no problems. (And without the flash.) The only thing I've done out of the ordinary recently was synching my studio lights with the PC outlet.

So I'm stumped. Has this happened to you? Anyone have any ideas? Or will I wind up schlepping down the Jersey Turnpike Monday morning?

[/ QUOTE ]

What happens when you try to use the camera's internal flash? If it doesn't work either then you **might** have done some internal damage to the camera using it with the studio lights. Some of them have a high trigger voltage that can damage the flash firing part of the camera's shutter. I believe the maximum you're safe in putting across the contacts is something like 6 volts. Most people either use a safe sync unit or radio trigger like the pocket wizard.
Hopefully that's not the problem as it will reguire a trip to Canon service and some expense.....