Baffling HDMI dropout during live stream

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jaketgfilm

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  • Joined: Thu May 25, 2023 12:59 pm
  • Real Name: Jake Tinkler Ganley

Baffling HDMI dropout during live stream

PostThu May 25, 2023 1:15 pm

Hi all,

I was working as a camera operator for a live stream awards ceremony yesterday. We had four cameras: a static Sony FX6, an operator with Sony FS7, operator with Ursa (mini Pro? Unsure), and myself on my Pocket cinema 4K. All cameras were run through SDI drums to the Vision Mixers Blackmagic panel (approx 30m of cable), and my BMPCC4k was converted with a Blackmagic HDMI>SDI adaptor.

My job was to capture shots of the crowd facing away from the stage, and track award winners as they walked onto stage to receive their award. Facing the audience was fine, streaming video smoothly to vision mixer, however when I turned my camera to face the stage, video would drop in and out on both my monitor (being run through the HDMI>SDI converter) and the vision mixers monitor. If I turned the camera to face the crowd again, no issues at all. The issue only occurred when facing the stage.

We tried many things, including swapping out the converter for a different converter, using a decimator, swapping cables, swapping monitors. We then tried moving the camera around the room, and no matter where we moved it, when facing the stage we would experience dropout. Eventually we had our setup down to just my pocket 4K running HDMI into another operators SmallHD monitor, where the image on the monitor would drop in and out. We tried lots of different HDMI/SDI cables, so clearly the issue is with my HDMI port. For the shoot, fortunately one of the other operators had a spare pocket 6k pro handy, and I used that for the shoot. But none of us, or any of the AV guys could work out what the issue is.

The only explanation I could think of was that there was some interference coming from the stage that was affecting the HDMI port. We had DMX, wireless comms, audio, and I'm sure other wireless systems in play on the day so the only thing I can think of is that these were somehow interfering with my HDMI port, maybe it is poorly shielded?

I will admit to being very confused and slightly out my depth when it comes to how different wireless solutions can impact hardware, and my guess could be completely off, but I just cannot find an explanation for this problem. Any input would be extremely helpful as I'd love to avoid situations like this happening again in future.

Thanks in advance!
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rick.lang

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Re: Baffling HDMI dropout during live stream

PostFri May 26, 2023 4:43 pm

HDMI
https://r.tapatalk.com/shareLink/topic? ... source=app

It does appear you have isolated the problem to the unshielded HDMI connection. The links in that thread above do identify some shielded full-size HDMI connectors that should fit the BMPCC4K.
Rick Lang

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