GH4 Horizontal Banding on GH4

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Darkwing Productions

Member
I have a shoot coming up tomorrow at a small boutique store, which is lit solely using overhead LED track lights. No matter what settings I use on my GH4 + Nikon 28-70 f2.8 combo (4k or 1080p, 24fps or 30fps, different color profiles, etc.) I kept getting these horizontal lines. In the sample videos below, you can see what I'm talking about. The only way I was able see any difference in the "banding" was by adjusting the shutter speed.
From what I've read, the banding is attributed to either the ambient lighting or shooting in low light (which is the case here). There'll be more light tomorrow for the actual shoot, but I'd really like to get to the bottom of this. When I used to shoot with my Canon T3I, the only time I remember getting those lines was under certain fluorescent lighting - it didn't seem to have anything do with the ambient lighting.
 
Since you're shooting today it's probably too late, but for future reference what you want to use is the Synchro Scan setting in the GH4. Turn it on in the Motion Picture part of the menu. This lets you fine tune the shutter speed in much smaller increments than normal, so you can find a shutter speed that matches the frequency of the light to eliminate the banding you are seeing.

Here's the relevant section from the manual:
Lp0Dt3j.png
 
... but do understand, with LEDs, sometimes there is no shutter speed that'll make it go away. Sometimes LEDs just screw up a rolling shutter camera's image. You can frequently find a shutter speed that will eliminate it, but not always.
 
Barry_Green said:
... but do understand, with LEDs, sometimes there is no shutter speed that'll make it go away. Sometimes LEDs just screw up a rolling shutter camera's image. You can frequently find a shutter speed that will eliminate it, but not always.
Click to expand...
Oh, that's because some LEDs use PWM for dimming. Sucks when that happens.

Darkwing Productions said:
I was able to find a shutter speed that worked, and since it was a locked off shot, it wasn't much of an issue. Still frustrating though.
Click to expand...
Yea, unfortunately, it's unavoidable. As long as there's artificial light running off AC, you'll always have to bear that in mind.
 
Careful observation of a histrogram will often reveal flicker. Waveform is even better, but nothing beats playback, especially on a large monitor.

Many users prefer to shoot slomo in 60p, & re-time in post, but I'm an ardent fan of VFR in large part for it's ability to playback at 24p in-camera so I can quickly check for flicker, & strobing.
 
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