Godox TT350S flash intermittently not firing with Sony A7IV

[Yee Peng]

Hi all,

I am new to Sony A7IV and am trying out the new focus bracketing mode with the new camera body's firmware 4.00.

I set A7IV to focus bracketing with the following settings.

* narrow step of 1

* 30 shots

* Interval 5s or even 10s per shot

* Exposure smoothing on

* Godox TT350S in high speed sync mode. Manual exposure 1/16 power. Rechargeable battery with full charge. Flash unit securely inserted into camera body's hotshoe and tightened. Camera body and flash unit are new so the electrical contacts should be good.

* Sony 90mm F2.8 macro G master lenses

* Full Manual mode: F2.8 aperture, 1/500 shutter speed. ISO 100.

I repeatedly tried many rounds of bracketing with same settings above but I always noticed 2 problems:

1) The flash will intermittently not fire (3 to 4 shots out of 30) even though the flash test light was always lit indicating flash has recycled and ready to fire.

2) The exposures of some shots will look slightly darker or brighter compared to other shots. Sometimes the top portion of the shots will look slightly darker.

I suspect the following possible root causes:

1) Sony focus bracketing feature is buggy

2) The Godox flash isnt very compatible with A7IV. But I have checked Godox compatibility document and have no problem there.

3) Flash overheating (Godox over temperature control kicks in). But according flash user manual if this kicks in I should see an indicator on the flash LCD but there wasnt any.

4) For the uneven exposure, could it be the A7IV sensor or shutter speed couldnt keep up with high speed sync?

Please advise. Thanks.

Wong Yee Peng

[michelb]

 

e-Front Curtain Shutter on or off ?

This feature can cause uneven exposure

[Cameratose]

Try both the camera and flash in full auto and see if it still does the same thing. Odds are you running everything in manual is causing some conflict. Images that are darker on one half are the result of an out of sync shutter/flash. I've used a 350S on my A7 IV and have never had a problem, but I have never tried it with focus bracketing