DV & FCP not broadcast standard?

[Eric A. Anderson]

I am currently in the final stages of editing a documentary that I shot on an XL1 and have been editing on FinalCut Pro. It will be mastered onto DigiBeta via a Miranda DV bridge to the SDI inputs on the deck.

The producer is saying that we need to do an on-line edit to make it meet the broadcast standards. I was thinking we would only need color correction.

Here is their explanation of why you can't broadcast things with FCP & DV... is this true? Since DVCPro is also a DV25 format how can it get around the 480 vs. 486 problem?

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I am writing in regards to the proposition that Final Cut Pro creates a master that would comply with PBS national standards.

Final Cut Pro (and Avid Xpress DV) both capture digital video at the
native DV25 frame size: 720 x 480 pixels of active picture area.
Television standard on this continent is 720 x 486 pixels of active
picture area. This means that the native size and output of both FCP
and XDV are substandard. Even output to a non-dv format can result in 6
lines of active picture in which black levels are out of compliance
(super black instead of 7.5 IRE). When you capture DV source material
into an Avid Media Composer the system adds two lines of 7.5 IRE black
at the top of the image and four lines of 7.5 IRE black at the bottom.
This results in a master that will actually pass standards compliance
with PBS national, which is why so many DV projects are on-lined on
Media Composer. It is also the reason that the Automatic Duck software
application which converts Final Cut projects into Avid Sequences has
become so popular.

In so far as color correction is concerned: DV cameras as a class
operate without "set-up" which is to say that black levels and
highlights on captured footage are routinely out of compliance with
broadcast standards. Blacks fall around 12 IRE instead of 7.5 IRE.
Whites and highlights record near 108 IRE instead of 100 IRE. The
entire luminance range floats. Every shot in a DV originated program
needs to be corrected to comply with broadcast standards. Simply
clipping luminance levels doesn't fix the problem because it just saws
off the white peaks, creating blooming, and the blacks stay grey. This
is patently obvious if you view FCP or XDV output on a waveform monitor.

[Rob Lohman]

That sounds right. In theory I would suspect and DV to another
(analog) format to include these 6 pixel rows @ 7.5 IRE for NTSC.
It sounds like it doesn't.

I think normally the TV station worries about this. So they accept
a DV tape and do whatever they need to do to make it broadcast
compliant. But his reply sounds good to me. However, I'm not in
the broadcast or NTSC market.

[Jeff Donald]

I have looked at the output of FCP on Leader and Magni waveform monitors and they meet NTSC spec in regards to IRE values. I suspect that PBS's differing results are caused by inexperienced editors switching sequence settings, capture settings or editing in the wrong color space.

My understanding is that DV conforms to CCIR 601 (the same as D1) and is legal for broadcast. The extra 6 lines of black would be subject to the black values produced at the time of transfer to a 486 format. If the set-up is wrong, the extra 6 lines (as well as all black levels) will be off as well. PBS's decision is probably based more in aesthetics than NTSC broadcast requirements.