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Old February 4th, 2013, 05:28 AM   #1
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Canon 7D for broadcast ...

Dear All,

I am having a few issues with a Canon 7D

The images straight out of the box are superb and are required for use on TV in Europe. Here's how I work with them;

25fps > convert to ProRes422 using MPEGstreamclip > edit using FCP v7 (ProRes422) > export to full size stand-alone clip using the H.264 codec.

Now, at some point I believe that the final clip needs to be reconverted using MPEGStreamclip but the broadcaster has yet to send me any details. I have been advised that attention needs to paid to; field dominance, interlaced scaling and/or deinterlace video.

I would be grateful if anyone had any thoughts on this process?

S
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Old February 4th, 2013, 11:06 AM   #2
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Re: Canon 7D for broadcast ...

I'm not sure why you would go from camera H.264 to ProRes and then back to H.264. This will cause a quality hit on the footage, ESPECIALLY if you're going to reconvert yet again after this. I would render out your stand alone clips from FCP7 in the same format you're editing in, ProRes422. Keep these clips as your "archives" and then convert them to what the broadcaster needs when you find out.

Since you're shooting 25p, I don't see field dominance, or de-interlacing to be relevant to your situation. And as far as the scaling goes, why scale down from the original HD? Does the broadcaster need SD 60i or something?

Remember, the fewest format / size conversions will maintain the best image quality. Keep everything in ProRes as long as you can and then go to the format the broadcaster desires. More info on the required specifications might help as well.
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Old February 4th, 2013, 08:02 PM   #3
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Re: Canon 7D for broadcast ...

Quote:
Originally Posted by Stuart McAlister View Post
The images straight out of the box are superb and are required for use on TV in Europe.
TV in Europe comes under the umbrella of the EBU, and my understanding is that no DSLR in video mode is cleared for broadcast, not for unrestricted use on major channels, anyway. Have you checked it is indeed acceptable for your intended client? (And different types of programming have differing recommendations.)

And before you think it's over strict ("The images straight out of the box are superb.....", as you say, the reasoning is down to aliasing - which DSLRs are plagued by to one degree or another. And the danger is that they can be unnoticeable at first generation, but act to screw up a broadcast codec chain such that the pictures *may* be severely degraded by the time they get to the viewer. Whilst pictures looking initally similar from a higher spec camera may survive the broadcast route far better.

Best analogy I've heard is with food poisoning. ( :-) ) It compares aliases to bacteria - you can't detect them as you eat what may seem to be a superb meal - but that doesn't mean they don't have the capability to have a very bad effect later!
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Old February 5th, 2013, 05:06 AM   #4
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Re: Canon 7D for broadcast ...

Quote:
Originally Posted by Stuart McAlister View Post
Dear All,

I am having a few issues with a Canon 7D

The images straight out of the box are superb and are required for use on TV in Europe. ...
Now, at some point I believe that the final clip needs to be reconverted using MPEGStreamclip but the broadcaster has yet to send me any details. I have been advised that attention needs to paid to; field dominance, interlaced scaling and/or deinterlace video.

I would be grateful if anyone had any thoughts on this process?

S
Like David said, the 7D is not an accepted broadcast camera, but assuming you found an in:

As far as the EBU guidelines are concerned deinterlacing is unacceptable, they prefer delivery in the original format or interlaced. If they are okay with 7D video, they should be okay with 25p.
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Old February 6th, 2013, 08:45 AM   #5
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Re: Canon 7D for broadcast ...

You also might want to compare using the Log and Transfer Plug in for Canon EOS to the Mpeg Streamclip results when going to Prores. I have found MPEG Streamclip to be fast but not as clean in other situations and think this would be true in your case as well. I also find that Compressor is slower but cleaner on output as well.
As far as whether the 7D is Broadcast quality this can be very technical. For full programs which go through quality checks before broadcast it may fail the test. For news pieces or shorts it may not matter as much. Content can overcome almost any technical objection but don't count on it pleasing the techies just because it looks good to your eyes.
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Old February 6th, 2013, 11:55 AM   #6
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Re: Canon 7D for broadcast ...

I do deliver 7D and other DSLR newsfootage to broadcasters here in the Netherlands a few times a week. Certainly it's not ideal but with newsfootage the content of the footage is far more important than the picture. I do load the .MOV files (1920x1080 25p) 1-1 in Sony Vegas Pro 10 and after a raw cut I do render them out as XDCAM EX MXF (1920x1080 50i). That format is accepted by all.
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Old February 6th, 2013, 12:25 PM   #7
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Re: Canon 7D for broadcast ...

If the subject is important enough, broadcasters will accept footage from mobiles. They will them excuse the abysmal quality by a text overlay saying something like:

'We apologise for the poor quality images supplied by an amateur cameraman.'
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Old February 6th, 2013, 12:27 PM   #8
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Re: Canon 7D for broadcast ...

Quote:
Originally Posted by David Heath View Post

Best analogy I've heard is with food poisoning. ( :-) ) It compares aliases to bacteria - you can't detect them as you eat what may seem to be a superb meal - but that doesn't mean they don't have the capability to have a very bad effect later!
I like that analogy David. Maybe it should be considered in the context of bacteria in food that gets worse upon each reheat/cool cycle after it's initial cooking!
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Old February 6th, 2013, 01:53 PM   #9
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Re: Canon 7D for broadcast ...

Quote:
Originally Posted by Gabor Heeres View Post
I do deliver 7D and other DSLR newsfootage to broadcasters here in the Netherlands a few times a week. Certainly it's not ideal but with newsfootage the content of the footage is far more important than the picture. I do load the .MOV files (1920x1080 25p) 1-1 in Sony Vegas Pro 10 and after a raw cut I do render them out as XDCAM EX MXF (1920x1080 50i). That format is accepted by all.
The standards for news footage is different to that on HD programmes. You're allowed a percentage of non standard material in a programme, but vast majority usually meet EBU standards. SD standards are different again and some HD channels are less demanding than others. The UK broadcasters usually want the gold HD standard.
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Old February 7th, 2013, 04:35 AM   #10
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Re: Canon 7D for broadcast ...

Quote:
... They will them excuse the abysmal quality by a text overlay saying something like:

'We apologise for the poor quality images supplied by an amateur cameraman.'
Ouch! That must hurt.
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Old February 8th, 2013, 09:01 AM   #11
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Re: Canon 7D for broadcast ...

Quote:
Originally Posted by Steve Game View Post
If the subject is important enough, broadcasters will accept footage from mobiles. They will them excuse the abysmal quality by a text overlay saying something like:

'We apologise for the poor quality images supplied by an amateur cameraman.'
I have never seen this.
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Old February 9th, 2013, 04:21 AM   #12
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Re: Canon 7D for broadcast ...

Usually news stations just use a chyron key that just says "Amateur Video" when referring to low quality video.

News Magazine shows on this side of the pond use 5Ds and 7Ds all the time.
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Old February 9th, 2013, 11:18 AM   #13
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Re: Canon 7D for broadcast ...

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Originally Posted by Jack Zhang View Post
Usually news stations just use a chyron key that just says "Amateur Video" when referring to low quality video.
I have seen YouTube clips shown all the time and never with a disclaimer. Maybe back a few years ago when it first started, but in 2013, I haven't seen any apology for lack of quality for any source.
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Old February 10th, 2013, 04:37 AM   #14
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Re: Canon 7D for broadcast ...

Dear All,

Thank you for your valued input.

Nate - the reason I convert to 422 is that the 7D footage is not the only material being used. It's a mix and match with other sources/formats so I prefer to start with everything on the same codec; the common denominator, so to speak.

Since posting, I have been informed by the broadcaster that they require 25fps (50 fields) interlaced and a colour sub-sampled at a ratio of 4:2:2.

I, too, have never heard or heard of the phrase 'We apologise for the poor quality images supplied by an amateur cameraman' being broadcast. However, 'Amateur footage' is often used but that is more along the lines of mobile phone images and not a well lit, clear sounding, beautifully framed and well crafted DSLR shoot.

News is a different beast and with organisations pushing their journalists to become one-man-bands (I am not in that bracket, I am just a cameraman/editor), many of them are equipping their field ops with DSLRs. They are a lighter and cheaper option and easier for hacks to learn. As far as the EBU are concerned, they will equip to suit their own requirements.

Gabor - I thank you for that tip. It is interesting to note that a fellow shoot/edit uses XDCam and that export codec is quite popular - no matter which format they started with.

So, food for thought and I thank you all once again.

Stuart
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Old February 10th, 2013, 07:59 AM   #15
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Re: Canon 7D for broadcast ...

How are you getting 4:2;2 from a camera codec that's only 4:2;0? Now broadcasters usually want 4:2:2 as the camera recording, of course this doesn't apply for SD, but it's usually the case for HD.
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