GH4 GH5 for broadcast in HD

A

abadseed2

Member
We are starting a BBC4 doc in April and are possibly considering using a GH5 for some of the shoots. We are thinking of using that camera because it would allow us to fly under the radar a lot of the time, we would be very mobile and require minimal crew.

The question is does the GH5 cut the mustard when it comes to the BBC standards.

I know that they require at least 422 50mbs IPB when shooting in HD. But does that mean that they require at least 200mpbs IPB when shooting 4K?

Finally and most importantly for us, would 150mbs downsampled to HD be good enough for broadcast?

Any thought would be much appreciated.

Thanks.
Aleks
 
Best thing to do always is speak to the commissioner to get their technical requirements. As far as I know even GH4 4k footage at 420 8 bit is acceptable for HD delivery (I seem to recall that 4k 420 downsampled to HD gives you 422 or even 444?) - someone correct me if I'm wrong.
So for HD delivery I would assume the GH5 would be more than good enough and that it would possibly qualify for the EBU's UHD Tier 2 - only possibly held back by bit rate of codec (150mb/s vs the recommended minimum of 200mb/s). Tier 2 is where vritually all cameras sit - the only one qualifying for Tier 1 as far as I know is still the ancient Sony F65.

Looking forward to lots of corrections on this post apologies in advance for any errors!

Steve
 
So you're thinking for a BBC4 strand such as Storyville? My understanding is that they are (or were) more flexible about standards. And also that things are in flux over there (and everywhere). I'd guess they've moved beyond the most-recent EBU R.118 revision I've seen, version 1.2, which is two years old. I'd guess that Tier 2, 2L, 2J have been updated. But the document is still worth a read, I'd say, for general background on this particular approach to ranking needs:
https://tech.ebu.ch/docs/r/r118.pdf

Then maybe dig up the BBC technical standards through this page:
http://www.bbc.co.uk/commissioning/tv/articles/documentaries

Then think about how much of your film you think --must be-- or --preferably will be-- shot on a low-profile camera. I mean: will you have any sit-down interviews, or will the whole thing likely be verite?

THEN dig up the proper contact at BBC4 or Storyville and, with a sense of how they did view things, ask how they view things now and expect to in the near future.

Note that my understanding of Storyville's standards comes from hanging with people at pretty-much the US equivalent, ITVS. But my further understanding is that the people over at BBC4 and Storyville are helpful and REALLY want to have technically-solid material come in without placing unrealistic budget burdens on the filmmakers.

OK, not a totally helpful response, but hopefully gets you closer to an answer...

Good luck and please please please let us know what you learn!

Jim
PS- like Steve, I eagerly await more insightful and informed info from other folks here...
 
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Wouldn't an external recorder cover the needs? Bigger and more obvious, but might get the job done.
 
And, of course, the real key is getting one's hands on a GH-5 by April. It's likely to only be sparsely available by then.
 
Thanks everyone. The EBU sheet seems to suggest that for Tier HD2L you only need 420 in progressive and 35mbits/s. Am I reading that wrong?

And yes, external recorder would make us 100% safe. It does mean having to rig the camera, through.
 
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