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Varicam footage captured at 5.6Mb/s or 13.9Mb/s – RANDOMLY – by AJ1200 in FCP
I was not sure which forum would be the best for this post, but any insights will be appreciated. We have been capturing 24p footage from a varicam with a Aj1200 deck into our Fcp 5.0 system. However, in some cases the captured tape will show up as a red “unrendered” clip in our 24p (actually 23.98) sequence.
I had followed the advice of Kenstone who recommended to use the Easy Setup 720p24 option in FCP. Often, after I close the log and capture window, set the Easy Setup to 720p24 again, and re-open the log and capture and capture the clip, it would capture correctly (ie: not show up as red or “unrendered” in our sequence). However, after a few tapes that have been captured entirely the “wrong” way, I became convinced that it may a be a deck issue.
These settings are the same for all of our media: Frame Size = 960×720; Compressor = DVCPRO HD 720p60; Audio = 16-bit, 48k; Field Dominance = none; Pixel Aspet = HD (960×720).
The settings that vary are Video Rate and Data Rate. Half came into our system “correctly” at 23.98 (5.7 mb/sec) while the remaining footage is at 59.94 (13.9 mb/sec).
We will have to return the deck in 12 hours, and it appears that the more tapes we capture the more it seems we need to recapture (and pray it is doing it at 5.7Mb/s). So we are now frantic! Prompt reply will be greatly appreciated! Please help us — is this a deck setting issue?
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10 Replies
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I’ll bet your problem is that pn some tapes you’re beginning the capture on color bars! Bars are always recorded at 59.94 irregardless of the frame rate you’ve set, so FCP thinks it’s not a 24p tape. Fix is to begin import after color bars.
Unless you’re making downconverts, the color bars are useless in digital anyway, there’s no proc amp like settings to adjust “level” and it only causes the type of confussion you’re having now. You might consider telling your crews to skip it, just fast forwartd a few seconds into the tape and start shooting!
Hope this helps,
JS
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Now I was going to do the test — thank you John for educating me!
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Hi, John!
I suggested in a professional forum that we do away with color bars with our HD cameras and was soundly hammered into the ground by other forum members.
We are indeed slow to change in this business; I think the :30 color bars at the head of the tape are a hold-over from two requirements; the need to set up analog machines and the old film days when scratches and damage was more likely to occur at the head and tail of the tape.
I’ve never seen any kind of drop out or other problem at the head of an HD video tape, but I still slavishly record the :30 color bars.
Perhaps I’ll show some real courage and move to :10 of bars!
Good shooting!
Leo
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[Leo Ticheli] “Perhaps I’ll show some real courage and move to :10 of bars!”
You rebel, you.
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Don’t do away with recording bar as they serve much more than would appear.
In the field they are the fastest method to verify unity throughout your signal flow chain. From calibrating field monitors to verifying signal flow etc color bars are a useful and benefical video test signal.
Futhermore the can be use in post for verifying proper recording levels in the event you recorder is misaligned or has problems.
One last note in post or during digitizing verifying bars video level playback against actual video can verify if there were issues or problems relating to the exposure, recording level etc etc. Unity throughout the chain need to be verified with a standard video test signal which is what color bars can serve as.
So in nutshell don’t just give up on not recording bars on your tapes.
And one last thing allowing a short break between tape reloads to record bars give the crew a short period to take a break during the course of a long production day as well as allowing the DIT or video engineer to QC recording tapes during the reload process.
There is no sense in forcing non stop shooting to occur without the chance to validate and QC the recordings and signal flow through the production shoot unless you like to find out all the errors later in post.
Tony Salgado
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I think bars have limited usefulness these days, but I agree with Tony for the reasons he has given also.
On a multicam XDCAM HD shoot I had over the summer though, I found myself in a new head-scratcher when I was editing, I saw that half my operators rolled bars on the XDCAMs! I was like “now what am I going to do with these!?”
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Unless you’ve discovered a monitor that automatically sets itself up properly under all viewing and lighting conditions, there’s still a vital reason to have bars at the head of a tape.
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Hi Mike,
I’m not sure we need to do things the way we formerly did.
In the field, you don’t need to record the bars to setup the monitors; if you need do much at all. We’re using the Panasonic 17″ LCD’s in the field and they are very stable.
In post, the monitors are setup by the engineer and we never, and I really mean never, have any kind of system drift from job to job, much less tape to tape.
I intend to continue recording bars at the tape head, but am switching to :10.
If I were shooting on rental gear or for post outside my own shop, I would record a full :30.
Good shooting!
Leo
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Has anyone ever seen a bad set of ‘digital bars’ ?
Colour bars are from an age of analogue signal levels and were very important.
Digital test signals should be about error correction issues in the digital path bars are no good for that.
For a camera i would much rather see it pointing at a resolution chart than a perfect digital bar generator.
So yes it is at least a valid debate.
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Other things that need to be thought about.
If you are using the FW Capture setting that you reference- FCP will default back to the 59.94 frame rate when ever there is a TC break, a Cadence break (you have shot some frame rate other than 23.98)
The other issue is that “capture now” is not often smart enough to determine these changes so the system returns to the 59.94 frame rate as it is recorded on the tape.
gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
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