topic Re: occasional overexposure with Speedlites in Speedlite Flashes

occasional overexposure with Speedlites

arlin411 — Mon, 24 Jul 2017 22:56:22 GMT

I've seen several threads about exposure issues with speedlites but none that are quite what my issue is.

I have a 580EX and a 600EX-RT. I use them on a 5D Mk II and a 70D. Regardless which flash and which body, the same thing occurs. I shoot in manual exposure with the flash on-camera on ETTL, no compensation. It'll be exposing fine then it will start to over-expose by a stop or two. I've found that if I turn off both flash and camera then fire them up again the exposures will be correct.

It doesn't do this often--maybe once in 100 shots, but if that shot was THE shot then it matters!

I'd appreciate any thoughts on this.

-Arlin

Re: occasional overexposure with Speedlites

diverhank — Tue, 25 Jul 2017 20:57:43 GMT

If it happens only 1 out of 100 and doesn't get worse I wouldn't worry about it.

Apparently there was some problem with the ETTL function...that couldn't properly measure the correct light output required. Maybe there is some miscommunication between the camera and flash...

or, if you've been using Pocket Wizards, I read that it can potentially causes damages to your flash IGBT circuit which regulates the light intensity of the flash. Without IGBT, the flash will output at full power, therefore overexpose your images.

Re: occasional overexposure with Speedlites

arlin411 — Tue, 01 Aug 2017 21:48:30 GMT

If it were just the one shot in 100 it probably wouldn't be such a big deal, but once it starts over exposing it continues to until I do something about it, like turn off the flash and turn it back on again. So if I don't check the LCD regularly I could lose a whole sequence.

I don't use Pocket Wizards.

Re: occasional overexposure with Speedlites

Tim — Fri, 03 Nov 2017 22:00:17 GMT

Hello arlin411,

I understand that your Speedlite 580EX and 600EX RT overexpose images when used with your EOS 5D Mark II and EOS 70D.

You mentioned this occurs while shooting in Manual mode. Are other modes susceptible to the same overexposure? If possible, you might try shooting in Program mode to see if the same thing occurs with either camera.

Re: occasional overexposure with Speedlites

RobertTheFat — Sat, 04 Nov 2017 01:58:23 GMT

If you have an E-TTL camera and your flash is set to TTL mode, you will get severe overexposure.

Re: occasional overexposure with Speedlites

Waddizzle — Sat, 04 Nov 2017 12:12:04 GMT

@arlin411 wrote:
If it were just the one shot in 100 it probably wouldn't be such a big deal, but once it starts over exposing it continues to until I do something about it, like turn off the flash and turn it back on again. So if I don't check the LCD regularly I could lose a whole sequence.

I don't use Pocket Wizards.

If you recompose shots, then it could be your metering technique.

Hopefully, you won’t get the chance, but the next time it happens, check that the camera is still communicating with the flash. Make sure that there is no foreign debris on the flash shoe to cause a bad connection.

Finally, but I gotta ask. Are you locking the flash onto the hot shoe? I know a guy who wasn’t and had problems. ME.