Speedlite 580EX II in E-TTL mode flashes after shutter close on EOS 550D

[jan-san]

Hello everyone,

I'm having a weird problem with a Speedlite 580EX II I recently bought used.

When setting the flash to E-TTL2 mode, it seems that the flash goes off after the shutter has closed - at least that's what I assume happens because when I tried taking a picture of a mirror with the flash active, I wouldn't see any afterglow of the flash lamp on the picture. I'm using the flash as Master directly connected to the camera flash socket.

I tried all shutter sync options (1st/2nd shutter/hi speed), and the result was the same in all cases.

When I set the flash to manual mode however, it seems to be perfectly timed with the shutter.

Do you have any suggestions on how to overcome this?

Any help will be greatly appreciated.

Best,

Jan

[Skirball]

You're in master mode?  In master mode you can have the master flash fire as part of the overall exposure, or only as a preflash to trigger the slaves.  It's possible you have this mode set.  Once in Master mode, press the Zoom button and cycle through the options to make sure that Master Flash is On.

[jan-san]

Hi Skirball,

Thank you very much for your quick reply.

The preflash option was deactivated already, and I also tried setting the flash to stand alone mode (instead of master), but the result is still the same.

Any other ideas on what could be the issue?

[Skirball]

Bummer, I thought it'd be an easy solution.  Guess we'll have to walk through this:

So, you can see the flash with your eyes when you push the shutter, but it doesn't show up in the picture?  Or the flash doesn't work at all in eTTL mode?  If it's the former then I'm at a loss for explantion, either it's stuck in master mode without flash or the timing is way off.  You said that you have it in the camera's hotshoe, not using a third party trigger, correct?

Which camera shooting mode are you using?  Just to be sure, use Manual or Av until you figure out what's wrong.  Did you check your Flash Exposure Compensation (FEC), just to make sure that's not turned all the way down (though you would still be able to see something).

[RobertTheFat]

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@jan-san wrote:

Hi Skirball,

Thank you very much for your quick reply.

The preflash option was deactivated already, and I also tried setting the flash to stand alone mode (instead of master), but the result is still the same.

Any other ideas on what could be the issue?

---

One other thing to consider is that the E-TTL algorithm is strongly biased to avoid blown highlights and will shut the flash down as soon as it sees the bright spot begin to appear in the mirror. So a better test might be to point the flash at the ceiling when you photograph the mirror; E-TTL is much more tolerant of the effect of bounce flash, which tends to light a scene more evenly.

[JerseyTom]

Your flash is probably set to second-curtain mode

[jan-san]

Hi JerseyTom,

Thank you for your suggestion.

Unfortunately I sold the flash in the meantime, so I can't try it out any more.