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Broadcast Levels
Every week we do a show that is captured from Beta SP through a DV converter (DataVideo DC-10) into FCP and then output the finished sequence to DVCAM (DSR-40). We are getting complaints from the dub house saying that the video levels are too hot. We thought we’d fixed this by using “Joe’s Broadcast Legalizer” filter in FCP, but the dub house is saying that the image looks milky now with the filter and the video levels are still unstable.
Help! Any suggestions, thoughts….
Thanks,
the Beev -
3 Replies
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Can can’t just “magically” fix things and make the levels OK my slapping on a filter. Oh my, no no no.
You need two things:
1) An editor skilled with onlining a show, and setting it up for broadcast specs. If you want to do this, you need to get training. Then you adjust each shot…shot my shot…by using the 3-way color corrector or other tools.
2) An EXTERNAL waveform/vectorscope. The built in one is not good for this. Recently it was discovered that the scopes don’t read any video OUTSIDE picture safe. THAT IS MAJOR.Editing for Broadcast is big….and being properly trained is a big necessity. There is no filter that will “make it good” and ready for broadcast. It may help, but you need lots more.
Shane Ross
Alokut Productions
http://www.lfhd.net -
you need to identify where the bad levels are originating
if its the source footage then you need to get a new shooter
if its coming out too out from the BetaSP then you need to pull the levels down a bit (you can use the built-in process controls or put it through a proc amp)
likewise the DV converterif its something you’re doing to it in the timeline that is causing the problem then you need to figure out what that is and adjust your methods accordingly
and yes, if theres nowhere or no way to fix at source then you should use the colour correction filters
and very last step would be to throw the Broadcast Safe filter on there just to ensure that nothing is peaking too higha waveform/vectorscope is really an essential investment
good luck
Andy -
Based on FCP’s internal waveform monitor, both my Broadcast Legalizer and Apple’s Broadcast safe filter appear not to be accurate in FCP 5. The underlying controls do still work, just double-check their output against the scopes. A revised version of Broadcast Legalizer will be included in this month’s beta release.
There are some example images and screenshots on the Broadcast Legalizer page.
If your video is starting with a Luma floor of 7.5, possibly resulting from the BetaSP source, the default settings would cause the image to look “milky” because the floor would be further elevated above 7.5 IRE. (Depending on who you talk to, the 7.5 IRE floor may be a relic of analog and not necessary anymore.) Set the output Luma Floor to 0 (zero) and see if the results look better.
Because a frame-by-frame evaluation would be terribly slow and result in unpredictable shifts over time, my filter (and Apple’s) work from baseline assumptions about theoretical maximum video levels. Apple’s filter’s strategy is to clamp or roll off out-of-range values. That leaves middle image values untouched but I think it unnaturally over-compresses the highs and lows. My method compresses the overall frame to fit within the accepted broadcast-safe range of 7.5-100 IRE.
Joe Maller
http://www.joesfilters.com
http://www.fxscriptreference.org
Joe’s Filters and The FXScript Reference
for Final Cut Pro and Final Cut Express
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