D700 TTL metering gone awry :(

[Davi]

Asked about this on Talk Photography but haven't got anywhere so far.

Basically half way through an impromptu shoot a few weeks ago, my D700 fitted with Nissin di662 suddenly started underpowering the flash. One minute everything was fine, next every shot is way too dark. Sticking the flash on manual and I can get it to blow the exposure no effort. Sticking the flash on a D60 and it exposes perfectly, so the flash is fine! Using the built in flash on the D700 and again, exposes fine! It is only the Di622 on the D700 that causes an issue. Any ideas? D700 is brand new really, so I'm not fully up to speed and may well have nudged something?

Just hoping it's not broken already

[SamHH]

It's not the flash exposure compensation is it?

[Simpo Two]

Did you change any settings to provoke the correct/incorrect difference?

Oddly enough I was fighting a troublesome CLS combo yesterday so you're not alone!

[14-7]

Although not a Nikon man myself my 7D has a setting for the external flash which allows you to under/over expose it. Have a scan through the menus.

[ian in lancs]

The flash compensation button on a D700 is on LHS of the lens mount. The one with the lightning symbol on it. When its been set a little symbol will appear under the shutter speed on the top plate. It looks like a lightning symbol with +/- next to it. The exposure compensation indicator is also under the shutter speed. That has just +/- on it. The other reasons for exposure issues are bright sun interfering and/or obscured gun sensor when remote triggering. Another problem would be either too fast a shutter or too small an aperture and therefore asking too much from the gun. Finally, is CSM Menu e3 set up correctly? Right channel(s), mode and compensation.

[Davi]

thanks for the responses To cover the questions and suggestions:

Flash compensation is set to zero, setting it to +1 still results in under exposure.

I've not knowingly changed anything between shots, but that does not by any means mean I haven't

ian in lancs said:

The other reasons for exposure issues are bright sun interfering and/or obscured gun sensor when remote triggering. Another problem would be either too fast a shutter or too small an aperture and therefore asking too much from the gun. Finally, is CSM Menu e3 set up correctly? Right channel(s), mode and compensation.

Sun was originally in the equation, but I removed it by trying again in the evening once it was down! Same result unfortunately.

Shutter speed / aperture I removed from the equation by setting the flash to manual and trying all strengths while keeping the aperture and shutter speed as original - the gun was able to completely white out the picture so in my mind it's not that - correct or am being nieve (again!)

CSM e3... haven't got a clue, I shall go and investigate right now

[Davi]

just checked the e3 settings, look fine, looked all through the flash settings and can't find anything obvious

[ian in lancs]

I assume the flash is OK and set up properly for the reasons you give.

Could try removing the battery from the D700 leave a while and then power back up (the IT call center favorite.....). Alternatively, set one of the CSM menu banks to factory default and trying again.

Whatever you do don't tell Nikon a non Nikon flash is involved....

[Davi]

ian in lancs said:

I assume the flash is OK and set up properly for the reasons you give.

Could try removing the battery from the D700 leave a while and then power back up (the IT call center favorite.....). Alternatively, set one of the CSM menu banks to factory default and trying again.

Whatever you do don't tell Nikon a non Nikon flash is involved....

Could that cause an issue then?! Hell I'd planned to get an sb900 anyway...

Will try the factory default and see what happens, definitely not the flash as it's now been tried on two other bodies.