07-24-2017 06:56 PM
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.
07-25-2017 04:57 PM
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.
08-01-2017 05:48 PM
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.