Emergency help-wedding tomorrow

[gjones5252]

I have been having a problem with my flash for a while. But i dont think it is with my flash i believe it with the user.
I have a 600ex and a 5dm3 and 5dm2.
Whenever typically for a wedding since the shots are moving fast and i do not have time to continually adjust stuff i put my cam on av and my flash on ettl.
with my 5d2 it works out just fine.
with my m3 tho it always seems to be off. like the flash all the suddent becomes under powered and isnt bounce flashing correctly(typically pointed up with gary fong)
whenever i change one setting it doenst seem to effect anything-i understand because it is in av and ettl both semi-automatic modes changing something means the camera will compensate for it.
but ill change flash to +1 to add more to it and it does nothing. ill change it to -2 no noticeable difference in image quality.
it makes me almost want to use my m2 more! so frustrating. it has been going on for a while now and i cannot seem to figure it out.
could it be a metering mode? did they change the way the m3 works with flash? is it a new ettl? please help with any ideas as i have a wedding tomorrow and this has been driving me mad.
thanks

[Harry Muff]

I'd start with the Custom Function settings. Default anything remotely related to flash or exposure.


Do you have Magic Lantern installed on either camera?

[bseitz234]

on camera? off camera? I assume one flash? flash sync? How far away are you trying to bounce? might it be firing at full power and just not able to do what you're asking of it? Kind of reaching a bit with these questions, but more info always helps.

[gjones5252]

magic lantern on the 5dm2 the one it seems to work on.
Did the wedding today and still had troubles.
It is like when in av and ettl the camera and flash do not communicate(may also be in other mode but just not manual) no matter how i change the settings it is still blown out by a considerable amount. And this is with iso static at 100. no and the aperture set at what ever applicable for photo. and high speed sync to ensure it can acquire necessary shutter speed.   
It is driving me nuts. in Manual mode on camera i can get it but i feel like i used to us AV and ETTL all the time.
probably me just not knowing how flash is working.

[kennephoto]

I've had similar problems with my 580ex II and my 5d2 it doesn't show focal length anymore for one.. I'm sure I messed up settings on the camera and flash guess I will have to figure out how to reset both to out of the box. I wonder if there is firmware for flashes off to google I go.

[Harry Muff]

Have you looked into the settings on the flash itself? Maybe a setting that only corresponds to later cameras like the 5D3?

[Jerrad245]

On my 5d3 with 580ex2 I always set my camera to av, no exposure comp, and then on the flash I set it to entitle with exposure compensation set between +1 and +2, just fix your ISP setting, I usually set mine between 400 and 800 depending on how much ambient light I want, should work just fine

[AJ]

Check whether flash metering (not camera exposure metering) is set to Evaluative or Average.  IMO, Average produces more even results. 

Evaluative has a highlight-protection mode built in which can lead to underexposure, especially when there are small reflective objects (e.g. jewelry).  In my experience, FEC doesn't help much with this.

[Zv]

magic lantern on the 5dm2 the one it seems to work on.
Did the wedding today and still had troubles.
It is like when in av and ettl the camera and flash do not communicate(may also be in other mode but just not manual) no matter how i change the settings it is still blown out by a considerable amount. And this is with iso static at 100. no and the aperture set at what ever applicable for photo. and high speed sync to ensure it can acquire necessary shutter speed.   
It is driving me nuts. in Manual mode on camera i can get it but i feel like i used to us AV and ETTL all the time.
probably me just not knowing how flash is working.

Thats because in Av mode the sync speed is limiting the shutter speed. You'll need to put it in manual and then use high speed sync on your flash. Only prob is now the power is reduced so you'll need to add about +2 FEC.