Hi folks,

I need some advice.

I recently shot a courtroom on my GH4. I needed a long roll (90 minutes plus) so I used the Panasonic 64gb card and set the camera to:

FHD 50 MBS

1920 x 1080 - 25p

Shutter speed 1/50

This is the problem. At the start, using mostly available light, everything looks fine. When people move in the frame it looks normal. But then we turned on 2 x 1k lights and things got weird. The vision becomes quite stuttering and people blur when they walk through frame.

Heres the vision : GH4 problem on Vimeo

I'm a bit baffled. My initial thought is that 50 mbps may have been too low a rate to allow the camera to write all the info, but I have no scientific basis for believing that. Otherwise, I'm at a loss to know what I did wrong to get that result.

Any advice is much appreciated!

Craig

Are the two different clips in the same file? I almost looks like it's shooting 15 frames per second at a really slow shutter in the second part. I've never seen anything like that with LED panels and my GH4 at 1080-60p or 4K UHD 30p.

Cheers,
Pete

It looks like you accidentally adjusted the shutter when trying to adjust the iris to compensate for the new lighting.

If you look in the motion picture menu, what setting is the exposure mode set to?