5D mkIII footage flashing when ISO is set manually

[fr3nchie]

Hi,

I noticed when filming with my Canon MkIII that the footage was strobbing/flashing (as if quickly switching between two exposures). Also the LCD screen switches between two exposures, perhaps every 5 seconds or so. It took me a while but I realised this only occurs when the camera is in manual mode and the iso is set to a value (not on Auto). I've tried everything, re-set all my preferences etc.. But the problem persists.

Has anyone experienced a similar issue, or have any idea as to what could be causing this?

Many thanks,
Marc

[Peter]

Is it same without a lens? I have the same with my 6D and with an old lens adapter.

[fr3nchie]

Hi Peter,

Thanks for your response. Yes I just tried filming with no lens and I get the same result..

marc

[Peter]

Can you upload a sample at perhaps youtube or here?

[fr3nchie]

I managed to fix the problem.

I have magic lantern installed on my camera to enable raw filming, there was a setting in there accidentally turned on. 'HDR shooting' which I'm guessing shoots two different exposures simultaneously..  

Thanks,

Marc

[Peter]

Yes. Hdr video will give you that effect.