Getting videos ready for TV broadcasting? (staying "broadcast legal")

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commercialguy

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Apparently there is a term known as "broadcast legal" or "broadcast safe" that you have to stay in or your video will be "bounced back" by the station and not aired. This is all new to me and I'm learning as I go.

I shot a low budget commercial for a local company that they plan to air on TV. I got all the deliverable requirements from the TV stations on the frame rates and aspect ratio that I'm preparing.

My big concern however is color calibration, gain settings, being broadcast legal. I can't afford a color calibrated monitor yet, or a Harris legalizer but I have DaVinci Resolve 9. Everything looks good on my computer and on others. Although the footage looks a little flat when converted to a Rec 709 LUT. I just get a little nervous doing anything too heavy with the color correction. I feel like I need to learn more about vector scopes and find alternative ways to stay broadcast legal. Any tips or advice for someone new at this?

Any good internet articles or books you could point me to?
 
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David W. Jones said:
Watch your waveform monitor and vector scope, they don't lie.
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Thanks David, but what should I watch for is my problem, lol. If they go out of range does that mean instant bounce back? I've watched hours of tutorial videos and they show you where everything is and how to color but don't talk much about being broadcast legal / broadcast safe. This is such an important thing to know, whether you're trying to air a commercial or your indie feature on demand somewhere.

I guess I need to do more research/digging.
 
Frank Glencairn:
It's a huge PITA unless you use some expensive external blackbox.

In Premiere there is a video limiter (for luma and chroma compression) and also a filter called "broadcast safe color".
But both only work to some degree.

Even if I set the limiter to 100/0 when I look at my Ultrascope log, there is still some scenes that go higher or lower.

If I set it to more aggressive levels, it stays within the legal territory, but looks like sh..t.

Would love to see a more professional tool in Resolve.
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from:
http://forum.blackmagicdesign.com/viewtopic.php?f=3&t=7701
 
I shot a low budget commercial for a local company that they plan to air on TV.
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^^ So if I may ask, is this for say....a cable TV company or similar?

I think the best thing to do is prepare the deliverable to the best of your ability, send it out and see what they say. I would be optimistic that it won't get rejected. LIke David said, just watch your scopes, don't have anything screaming over 100 on the waveform. I do the occasional Cable/regional spot, can't remember getting any station rejections. and for the most part when I see them on my home set they look pretty good.

I just get a little nervous doing anything too heavy with the color correction.
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I'm right there with you. Looking for more information on the subject but the internet is an endless resource.
 
Going out to ABC/Fox type channels. Thanks for the feedback, I'm still doing my research. Apparently the audio has to be broadcast safe too, so I'm trying to sort that out now as well.
 
When your video is rendered from your computer to any standard REC 709 component 8 bit or 10 bit 4:2:2 HD video codec, it is by definition "broadcast compliant". The safe quality standard is a codec with bit rate of 50mb/s or higher. REC709 codecs do not encode values outside of legal range as shown on the 0-100 IRE waveform monitor. Any values in your video that fall outside that range are simply not seen on a TV monitor.
What it will actually look like is another matter. To insure that it looks the way you want it to, you must color correct and grade your footage using a reasonably well calibrated reference monitor. The monitor should be at the very least calibrated by eye using a SMPTE REC709 reference color bar signal.
If you are finishing on a computer monitor, it should be set to sRGB color space if REC709 is not an option and calibrated to the color bar signal. If the monitor does not offer color space choices in its menus, it is by default sRGB.
However any consumer HDTV is already reasonably well factory calibrated to REC709 if you pick the "standard" LUT option from the menu choices and turn off any features like dynamic contrast. Current gen consumer HDTV's are almost all true 10 bit displays and you can adjust one using the built in SMPTE reference color signal from the HDMI output of your video camera. Unless you are running an expensive graphics grade IPS panel computer monitor, they are a superior choice for video reference. This is your best visual guide to "broadcast compliance".
 
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commercialguy said:
Apparently there is a term known as "broadcast legal" or "broadcast safe"...
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Yup. People write books about this stuff. One of the best, that I highly recommend to you, is Van Hurkman's Color Correction Handbook. Explains this, and a lot more, in an easily readable and informative style. Explains the stuff that you don't know enough to ask about yet, which IMHO is the mark of an excellent technical book.
 
I will put this simply because basically it is.

You need to ensure that Luma does not exceed 100% so that is very easy to control with Levels. eg drop your highlights (and whites) so nothing exceeds 100%

You also need to ensure that Chroma Luminance does not exceed 100%. Often you will find that Red channel is the culprit here.

Both these issues are easily controlled in Resolve and easy to do in Adobe Premiere as well.

Using Luma WFM And RGB Scopes...

In Premiere I apply 'Levels' effect to the clip or the entire program using an Adjustment Layer.

This automatically clips everything at 100%. I then use the White RGB In and Out controls to bring whites / highlights to 250-252 ish.

I then Use the Red controls if necessary to adjust Red Level


Do not forget to check your Black Levels. Too low and they will get rejected as well.

Do not use Broadcast Filter in Premiere. It really sucks.

Note: Levels in Premiere clips the "levels". eg hard clip. In Resolve one can do a lovely "soft clip" eg graduated clip.

YOu will be surprised that dropping and raising levels to make them BC legal does not have as much affect on what you see on your NLE system..but it does make a difference when broadcast. ( ie. a good affect)

Next Broadcast QC also looks at other stuff..interlacing errors, duplicate frames etc. Some issues that come form speed ramping and frame blending. Those issues need to be dealt with after theu find them.

And of course. "Audio "LOUDNESS". Use the Loudness specs they work with in your Loudness Meter.

Tip: Get a CC Grading reference book eg Van Hurkmans excellent one.
 
Shooter said:
I will put this simply because basically it is.

You need to ensure that Luma does not exceed 100% so that is very easy to control with Levels. eg drop your highlights (and whites) so nothing exceeds 100%

You also need to ensure that Chroma Luminance does not exceed 100%. Often you will find that Red channel is the culprit here.

Both these issues are easily controlled in Resolve and easy to do in Adobe Premiere as well.

Using Luma WFM And RGB Scopes...

In Premiere I apply 'Levels' effect to the clip or the entire program using an Adjustment Layer.

This automatically clips everything at 100%. I then use the White RGB In and Out controls to bring whites / highlights to 250-252 ish.

I then Use the Red controls if necessary to adjust Red Level


Do not forget to check your Black Levels. Too low and they will get rejected as well.

Do not use Broadcast Filter in Premiere. It really sucks.

Note: Levels in Premiere clips the "levels". eg hard clip. In Resolve one can do a lovely "soft clip" eg graduated clip.

YOu will be surprised that dropping and raising levels to make them BC legal does not have as much affect on what you see on your NLE system..but it does make a difference when broadcast. ( ie. a good affect)

Next Broadcast QC also looks at other stuff..interlacing errors, duplicate frames etc. Some issues that come form speed ramping and frame blending. Those issues need to be dealt with after theu find them.

And of course. "Audio "LOUDNESS". Use the Loudness specs they work with in your Loudness Meter.

Tip: Get a CC Grading reference book eg Van Hurkmans excellent one.
Click to expand...

Great info, thanks for sharing it!
 
Razz16mm said:
When your video is rendered from your computer to any standard REC 709 component 8 bit or 10 bit 4:2:2 HD video codec, it is by definition "broadcast compliant". The safe quality standard is a codec with bit rate of 50mb/s or higher. REC709 codecs do not encode values outside of legal range as shown on the 0-100 IRE waveform.
Click to expand...

No, you are mistaken!

Commercialguy, follow Shooter's advice.
 
commercialguy said:
Great info, thanks for sharing it!
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Seriously. It's posts like Shooter's that continue to make DVXuser such a great site/resource.

commericalguy, you were asking a bunch of questions on which camera to shoot with and/or purchase...etc. Did you ever settle on one? When your spot finally airs, we should all break out a global bottle of champagne and celebrate.
 
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