"Broadcast Friendly" color and bitrate necessary?

[Paul Hildebrandt]

Alright, I have a simple question that has been driving me nuts, especially with new cameras coming out, it just gets more and more complicated.

When shooting for broadcast HD television and cinema is it necessary to shoot on a camera that has 4:2:2 color space or better, and 50mbps, or will a camera that has for example 4:2:0 and 24mbps do just fine?

I'm going to guess the answer is you can shoot on the lower cameras and they will work just fine, for example Act of Valor which a lot of was shot on 5d's and I saw at my local theater. Also documentaries like hell and back again, and tons more television series that are broadcast on cable that I'm sure have been shot on DSLR's?

[Chris Medico]

Many broadcast clients will stipulate 4:2:2/50mb with 2/3" or larger imagers as the minimum video quality allowed for primary camera work. If you go with something fitting that combo you are in good shape.

You are OK to meet the requirements with an external recorder if the camera you like doesn't do 50mb internally. This does have a caveat though. If the dispatcher doesn't understand your setup they may deny you a gig because of your camera even though you have it covered via an external recorder. The people handing out the jobs are not normally technical people. They have been given a list of acceptable gear and if you don't have it then they move on to the next person on the call list.

If the broadcast market is something you are looking to most of your work for I would strongly recommend you buy a camera that is known to meet their requirements without anything extra. If this is something you will do here and there meeting the requirements with an external recorder is a viable option.

[Paul Hildebrandt]

Not speaking specifically about shooting footage and delivering it to a network, but delivering a final product to them to air. So say it was shot on a DSLR which does not meet those requirements, can one simply render these files into the required specs even though that is basically up converting it?

[Chris Medico]

Nope. Don't do it. You may get away with an upconversion here or there but they are getting very good at sniffing out that sort of thing.

Broadcasters have requirements for acquisition as well as delivery. You need to ask what they want before you start shooting. You could be making a very costly mistake if you don't.

[Brian Drysdale]

The post production costs of using say DSLRs can take away any cost advantage during the production stages. Major productions that use DSLRs will spend that money because they're getting other advantages, although those advantages probably no longer apply because of cameras like the C300.

However, if you're shooting for HD broadcasters who specify certain minimum specification, why risk rejection by the broadcaster? The BBC has rejected HD productions that it has commissioned because the producers used non standard cameras and the programmes didn't pass the quality control. Not all HD broadcasters insist on the higher spec, so it's a matter of matching up with their requirements.

Cinema is rather different to HD broadcast television, you can shoot on whatever you want, but you do need to sell it and get distribution.

[Eric Olson]

Originally Posted by Paul Hildebrandt

When shooting for broadcast HD television and cinema is it necessary to shoot on a camera that has 4:2:2 color space or better, and 50mbps, or will a camera that
has for example 4:2:0 and 24mbps do just fine?

Interlaced 4:2:0 is much more difficult to process than progressive 4:2:0. For whatever reason, much of broadcast HD is interlaced. For this and other reasons as mentioned already many broadcast standards specify a 4:2:2 color workflow.

In my opinion the difference between interframe and intraframe compression is more significant than the difference between 4:2:0 and 4:2:2 color spaces. High quality 4:2:2 can be recovered from 4:2:0 source using motion directed color inpainting techniques, whereas, there is no way to recover frame independence from a video that has undergone interframe compression. Frame independence is important because it allows use of filtering and superresolution algorithms that simply don't work with interframe compressed source.

If you get the color right in camera, then 4:2:0 is fine. This is why 4:2:0 is more accepted for electronic news gathering. However, if you need to color grade 4:2:0 source, it first needs to be upsampled to 4:4:4. The algorithms to properly do this with current technology are so computationally expensive that no one uses them. Recording with a 4:2:2 colorspace is a good compromise. If you want to guarantee your footage can be processed using advanced processing techniques in the future, you should also be recording with an intraframe codec.

[Nate Haustein]

Here's a question for the experienced:

I've been asked a few times recently by a few organizations to shoot some interviews and b-roll. The request was then to edit together about 5 minutes of raw highlights in order to send it off to various news outlets to be "picked up" for stories about the person/organization/event.

Speaking in general, and based of your experience, what are the best practices for:

• Recording? – I assume like said above: 2/3" CCD, 50mbps, 4:2:2 – does my AF100 with Hyperdeck sound adequate for this "public-generated" video content? Or should I be using a traditional 1/3" CCD camcorder that I own instead with or without the Hyperdeck?

• Delivery Format and media? – The easy part is using 50mbps+ and 4:2:2 on a local system, but what is the best format to send things in when storage space and bandwidth is at a premium? Full quality as captured? Transcoded to XDCAM? H.264? Also, whats the best media? DVD, USB Drive, FTP Link?

• Format of the clips to be delivered? – All one big file or a folder with individual clips? Any other lists or information to include?


***Again, asking these things in general as clients are wishing to send materials to sometimes dozens of news media outlets. What would be the best option if you could choose just one? Hope these questions make sense, and thanks for any info.

[Paul Hildebrandt]

Odd thing about this though, I just checked with a major PBS affiliate for national broadcast specs, and they specified that:

"HD program submissions are defined as those programs which have been acquired by cameras which have three sensor chips, each at least a 1/2” diagonal in size with a minimum frame size of 1280 x 720 and have been edited minimally as 3:1:1 -8 bit video"

Isn't 3:1:1 significantly worse than 4:2:0? Or am I not understanding that properly? Additionally, most new pro cameras are CMOS chips and not CCD's. So... how are new programs airing on PBS with these specs?

[Brian Drysdale]

The compression used on HDCAM is less than on the DSLR cameras and the consumer camera codecs, it's the compression artifacts that tend to be the concern of broadcasters. Having said that, the 3::1::1 used on HDCAM is less than ideal and that format is being replaced, although I believe they still shoot "The Big Bang Theory" with F900s, Also, there are a lot of HDCAM camcorders out there - these cameras can have working lives of 10 years. The continued use of HDCAM in the specs is historical and is, as they say, regarded as the minimum.

CCD chips do offer their own advantages and are used on many broadcast cameras, the upcoming Aaton Digital Penelope uses a Superr 35 CCD single sensor.

[Eric Olson]

Originally Posted by Paul Hildebrandt

Isn't 3:1:1 significantly worse than 4:2:0? Or am I not understanding that properly?

Assuming interlaced 1080i frames, then the field resolution of

3:1:1 HDCAM is 1440x540 for the luma and 480x540 for the chroma;

4:2:0 AVCHD is 1920x540 for the luma and 960x270 for the chroma;

4:2:0 HDV is 1440x540 for the luma and 720x270 for the chroma.

Straight out of the camera, they all look the same. However, 3:1:1 has a chroma format that is more suitable for interlaced material. In addition HDCAM is a 144mbps intraframe codec.

[David Heath]

Originally Posted by Paul Hildebrandt

Not speaking specifically about shooting footage and delivering it to a network, but delivering a final product to them to air. So say it was shot on a DSLR which does not meet those requirements, can one simply render these files into the required specs even though that is basically up converting it?

Simple answer - no. And yes, they can tell if you do it.

In the UK the guidelines are as defined by the EBU and via one document for camera testing and another for interpreting those results. See EBU TECHNICAL - News - Are your cameras tiered enough for HD?

I also agree with much of what has been said before - the above are "recommendations" - not "rules". That said it makes sense to comply with them, you could be saving yourself future arguments. They are a changing set and represent current best practice, whilst trying to give realism. HDCAM and 3:1:1 were state of the art not so long ago, but are now not. Existing equipment may still be allowed, but don't expect anyone to be buying it now.

Most important to realise is that the recommendations are only partly to do with picture quality out of the camera, a lot is how the images will survive the post and transmission chain. And that's why factors such as aliasing and codec are considered so important. No use images looking great at first generation if the aliases etc cause them to fall apart by the time they get to the viewer.

And that's why DSLRs tend to be frowned on so much by broadcasters. The raw pictures may look good enough, they may not stand up to chain.