Broadcast Legal? at DVinfo.net

Javier Urena · October 27th, 2005, 11:27 PM

I Read A Thread That Said The Colors From The Panasonic 24p Cameras Are Not "broadcast Legal."

Can Someone Explain What This Means And Are There Any Issues With The Xl2?

Tia

Glenn Chan · October 27th, 2005, 11:32 PM

Perhaps it's disinformation?

2- Many cameras can record colors that are not broadcast legal. (It may be that all DV cameras can do this.)

Many/all DV cameras will record "superwhites", which are values above digital white level. This is a good thing as you can pull this detail into the legal color range to gain more exposure latitude.
I believe they do this (instead of other methods) to maintain linear gamma by the time the image reaches the home viewer.

I presume the XL2 records superwhites like every other camera.

3- For NTSC, colors can be illegal for broadcast (which is different from DVD) if the composite value is too high. All DV cameras will record illegal colors too.
You could be dealing with these illegal colors in an online edit session (or color correction session), or you just let the broadcaster deal with those illegal values.

Chris Hurd · October 27th, 2005, 11:33 PM

If the content is compelling enough, then it's definitely "broadcast legal."

CNN runs tiny little 160x120 videophone clips -- small, choppy, grainy, ugly -- from overseas journalists fairly frequently. Make your video worth watching and nobody will care too much about the color!

Ash Greyson · October 29th, 2005, 12:17 AM

Broadcast legal is not 100% mandate but illegal colors will look terrible once they are put to tape, dubbed, compressed for broadcast and then decoded. Reds are the worst, especially on the DVX. The XL2 is the best 1/3" DV cam for broadcast colors. Almost every NLE has a filter or scope to help you with getting legal colors. Anytime you use a low shutter the colors will go crazy on the scope and are hard to curb.

ash =o)

A. J. deLange · October 29th, 2005, 01:53 PM

TV signals are broadcast with the composite video amplitude modulating the carrier with blacks increasing its amplitude (maximum power transmitted during the peak of the horizontal sync pulse which is blacker than black) and whites decreasing it. The composite signal is the sum of the luma and chroma. If the sum of the luma and chroma excedes the maximum allowable amplitude it will try to turn the carrier more off than off. This, of course, it can't do but if it turns it solid off quickly this results in spectral "splatter" i.e. noise in adjacent channels. That's why the FCC sets limits for the whitest white and the peak chroma signal amplitude (which is proportional to color saturation). NLE programs like FCP have filters which will take a signal which excedes the FCC limits and push them to within the limits.

Javier Urena · October 29th, 2005, 10:25 PM

Thanks for the replies. A TV editor told me it had to do with the reds, and that you usually have to pay a guy to color correct footage to broadcast standards. TV networks obviously have their own guys for this, which is why they can broadcast video from cell phones.

He said the feature on FCP 5 that makes the footage broadcast legal is a filter and a relatively new one. So he's not sure if it actually works or not, but I hope it does in order to avoid having to pay someone for that one function.

(I'm on a very tight budget.)

Steve House · October 30th, 2005, 08:29 AM

Don't know FCP but I'd exp[ect it to have colour correction tools in addition to the plugin filter. Adjust the colours so everything lies between 16 and 235 and you should be fine.

Greg Boston · October 30th, 2005, 09:43 AM

FCP does have extensive color correction capabilities and does have a video filter called 'broadcast safe'.

-gb-

Glenn Chan · October 30th, 2005, 03:37 PM

FCP doesn't show you the video values in a scale from 0-256, and it doesn't directly show you what the video values are. However, you can use the waveform monitors in it (which should not be confused with other waveform monitors, since FCP does its own thing [like all software waveform monitors]).
0% corresponds to digital black level, 100% corresponds to digital white level.

see http://www.kenstone.net/fcp_homepage..._nattress.html

You also need to watch out for the composite video levels as A.J. points out. I believe the broadcast safe/colors filter in FCP does this... the (110) or (120) preset should be appropriate.
You may need to get the broadcaster's document for their technical requirements to figure out the maximum composite IRE values you can have on your master.

October 27th, 2005, 11:27 PM	#1
Javier Urena Regular Crew Join Date: Aug 2005 Location: Los Angeles Posts: 67	Broadcast Legal? I Read A Thread That Said The Colors From The Panasonic 24p Cameras Are Not "broadcast Legal." Can Someone Explain What This Means And Are There Any Issues With The Xl2? Tia

October 27th, 2005, 11:33 PM	#3
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	If the content is compelling enough, then it's definitely "broadcast legal." CNN runs tiny little 160x120 videophone clips -- small, choppy, grainy, ugly -- from overseas journalists fairly frequently. Make your video worth watching and nobody will care too much about the color! __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

October 30th, 2005, 08:29 AM	#7
Steve House Inner Circle Join Date: Mar 2005 Location: Hamilton, Ontario, Canada Posts: 5,742	Don't know FCP but I'd exp[ect it to have colour correction tools in addition to the plugin filter. Adjust the colours so everything lies between 16 and 235 and you should be fine. __________________ Good news, Cousins! This week's chocolate ration is 15 grams!

October 27th, 2005, 11:32 PM	#2
Glenn Chan Inner Circle Join Date: Jun 2003 Location: Toronto, Canada Posts: 4,750	Perhaps it's disinformation? 2- Many cameras can record colors that are not broadcast legal. (It may be that all DV cameras can do this.) Many/all DV cameras will record "superwhites", which are values above digital white level. This is a good thing as you can pull this detail into the legal color range to gain more exposure latitude. I believe they do this (instead of other methods) to maintain linear gamma by the time the image reaches the home viewer. I presume the XL2 records superwhites like every other camera. 3- For NTSC, colors can be illegal for broadcast (which is different from DVD) if the composite value is too high. All DV cameras will record illegal colors too. You could be dealing with these illegal colors in an online edit session (or color correction session), or you just let the broadcaster deal with those illegal values.

October 29th, 2005, 12:17 AM	#4
Ash Greyson Trustee Join Date: May 2003 Location: Tulsa, OK Posts: 1,689	Broadcast legal is not 100% mandate but illegal colors will look terrible once they are put to tape, dubbed, compressed for broadcast and then decoded. Reds are the worst, especially on the DVX. The XL2 is the best 1/3" DV cam for broadcast colors. Almost every NLE has a filter or scope to help you with getting legal colors. Anytime you use a low shutter the colors will go crazy on the scope and are hard to curb. ash =o)

October 29th, 2005, 01:53 PM	#5
A. J. deLange Major Player Join Date: Jun 2004 Location: McLean, VA United States Posts: 749	TV signals are broadcast with the composite video amplitude modulating the carrier with blacks increasing its amplitude (maximum power transmitted during the peak of the horizontal sync pulse which is blacker than black) and whites decreasing it. The composite signal is the sum of the luma and chroma. If the sum of the luma and chroma excedes the maximum allowable amplitude it will try to turn the carrier more off than off. This, of course, it can't do but if it turns it solid off quickly this results in spectral "splatter" i.e. noise in adjacent channels. That's why the FCC sets limits for the whitest white and the peak chroma signal amplitude (which is proportional to color saturation). NLE programs like FCP have filters which will take a signal which excedes the FCC limits and push them to within the limits.

October 29th, 2005, 10:25 PM	#6
Javier Urena Regular Crew Join Date: Aug 2005 Location: Los Angeles Posts: 67	Thanks for the replies. A TV editor told me it had to do with the reds, and that you usually have to pay a guy to color correct footage to broadcast standards. TV networks obviously have their own guys for this, which is why they can broadcast video from cell phones. He said the feature on FCP 5 that makes the footage broadcast legal is a filter and a relatively new one. So he's not sure if it actually works or not, but I hope it does in order to avoid having to pay someone for that one function. (I'm on a very tight budget.)

October 30th, 2005, 09:43 AM	#8
Greg Boston Wrangler Join Date: Oct 2003 Location: DFW area, TX Posts: 6,117 Images: 1	FCP does have extensive color correction capabilities and does have a video filter called 'broadcast safe'. -gb-

October 30th, 2005, 03:37 PM	#9
Glenn Chan Inner Circle Join Date: Jun 2003 Location: Toronto, Canada Posts: 4,750	FCP doesn't show you the video values in a scale from 0-256, and it doesn't directly show you what the video values are. However, you can use the waveform monitors in it (which should not be confused with other waveform monitors, since FCP does its own thing [like all software waveform monitors]). 0% corresponds to digital black level, 100% corresponds to digital white level. see http://www.kenstone.net/fcp_homepage..._nattress.html You also need to watch out for the composite video levels as A.J. points out. I believe the broadcast safe/colors filter in FCP does this... the (110) or (120) preset should be appropriate. You may need to get the broadcaster's document for their technical requirements to figure out the maximum composite IRE values you can have on your master.