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Kona Card Capture – Framerate Issues
I’ve recently (within the last year) upgraded one of my FCP stations with a KONA 3 card installed to the 9.0.5 version of the AJA Control Panel software.
Since doing so I’ve noticed that when capturing standard definition material into Final Cut Pro, the frame-rate displayed by Quicktime Player for the resulting media files doesn’t always exactly match 29.97 fps. It’s usually off by .1 fps or so.
This hasn’t really affected our workflows too much since FCP and Quicktime player seem to do a good job of rounding things off to an even 30 fps anyway, but sometimes clients can be sticklers for details and I’ve found myself being asked to re-export some of these problematic files out of Quicktime Player and FORCE the frame-rate to 29.97fps.
I’ve looked through my archives of footage I’ve digitized from months and even a year back and this didn’t seem to be an issue back then. All of those old files seem to display 29.97fps exactly when viewed in QT player. The only recent change I can think of is the upgrade of the AJA Control Panel software.
Any insight? I’m trying to dig through FCPs settings and whatnot in the hopes that I’ll stumble over an explanation. So far no luck.
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Dan Charrington
Supervisor, Non-Linear TechnologiesMIJO
635 Queen St E. Toronto, ON
416-964-7539MacPro 8-core Xeon 2.8GHz, 10gb Ram, AJA Kona 3 SD/HD
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3 Replies
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I often see quicktime displaying weird frame numbers.I suspect the problem is within FCP/QT and the way it stamps metadata in the quicktime. FCP itself knows the correct rate but QT sometimes gets a weird rate.
This happens all the time when making quicktime conversions to H264 from FCP. The frame rate needs to be set manually and not rely on leaving it as ‘current’ or QT players reads it wrong.(This is true for 25 fps, not sure if universal or just a PAL bug)
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[Dan Charrington] “This hasn’t really affected our workflows too much since FCP and Quicktime player seem to do a good job of rounding things off to an even 30 fps anyway”
FC/QT doesn’t round the time-base to 30fps.
30fps is not any standard video Time-base, but 29,97.[Dan Charrington] ” the frame-rate displayed by Quicktime Player for the resulting media files doesn’t always exactly match 29.97 fps. It’s usually off by .1 fps or so.”
You don’t have to care what QTPlayer says.
Bring the files to FC and look what the Browser shows.[Dan Charrington] “but sometimes clients can be sticklers for details and I’ve found myself being asked to re-export some of these problematic files out of Quicktime Player and FORCE the frame-rate to 29.97fps.”
If there is a real issue, instead of re-exporting, try Conform to 29,97 in CinemaTools
rafael -
It is easy to say to ignore the frame rate in QT player. Which I always do. The bigger problem lists in programs that use the QT metadata for there transcoding software ie Flip Factory or Vantage.
I have been searching and searching on why QT player picks up the random frame rates. 29.98, 29.95, when capturing in FCP with Kona or Blackmagic and havent found anything. I am assuming it is a weird metadata label somewhere in the file that QT player isnt picking up. Similar to where QT player plays a 720×486 NTSC file back with square pixels when they are in fact .9.
Does anyone know the actual reason QT player is picking up this incorrect metadata?
Kevin Hotz
Director Of Operations
TJ&A
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