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720p30 through the kona?

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Justin Pokrant
720p30 through the kona?
on Mar 27, 2008 at 11:08:51 pm

Why doesn't the Kona 3 have a capture setting for 720p30?

The only way I could figure out how to capture at 720p30 is from the deck via firewire and the only way I could capture through the Kona 3 card was if I changed the capture preset to 720p59.94...

Am I missing something here? or is there a capture setting you can create in FCP to capture at 720p30 through the kona card that gets rid of the duplicate frames?

Also, when would you capture via firewire and when would you capture via the kona?

Please enlighten me!

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Scott Shucher
Re: 720p30 through the kona?
on Mar 28, 2008 at 7:01:42 am

I don't have an answer for you on "why Kona doesn't have a 720p30 preset", but I do have a word of caution.

I recently worked with Varicam footage shot at 720p30, and like you, the only way I could get the footage input and play out through a Kona2 was to capture with a preset of 720p59.94. This setting gave me dupilcate frames, but the footage played out cleanly through the Kona 2.

After capturing, I discovered an intermittent issue where some clips discarded the duplicate frames during the capture. In other words the video clip was half the original captured length, while the audio in the clip captured at normal length. As a result, what I got was a clip whose visual speed was doubled until the halfway point of the clip. The video capture then went black, while the audio continued to capture at normal speed.

So, for example, I'd capture a 10 minute clip with audio and video. Upon loading the captured clip I discovered the video would run at 2 times normal speed, then at 5 minutes into the clip the video would go to black, while the audio portion of the clip continued to play on until the normal end of the clip. This did not happen to every clip, and it did not seem to happen if I used "capture now"

I was capturing via firewire, and I never tried to capture via HD-SDI to see if the results were any different. At some point we just had to move forward with the project, so I never got a chance to try to figure out the capture issue with 720p30.

Bottom line, check your clips carefully after capture.

G5 2.5ghz DP, 2.5Gbyte RAM, FCP 6.0.2, OSX.4.11
QT7.3, Kona2 (v4.0) w/Kbox, Atto UL3D, Medea RTRX640, Huge MV 1.8Tbyte, Radeon 9800XT

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Justin Pokrant
Re: 720p30 through the kona?
on Mar 28, 2008 at 2:17:24 pm

Same thing happened here. We just finished a huge contract where 140 tapes were shot at 720p30 and captured at 59.94. I had to do it that way as I didn't have time to play around with capturing at 720p30. We are doing the exact same contract next year as well so I want to see if there is a better way to capture and/or shoot it.

Here are the details:

- shoot with a varicam,
- have to edit 720p material together with other 720p24 material that was shot 2 years ago, as well as stock dv footage supplied on beta, mini dv, and dvd.

Our deliverables are:
- all the final videos at 1080i60
- all footage shot delivered at 1080i60 either on tape or harddrive

What would be the best work flow for this?
This year we shot at 720p30, captured and edited at 720p59.94,mixed in 23.98 in the same timeline, upconverted the stock footage via compressor, or just streched it out in the timeline to fill the screen and added flicker filters due to time constraints, then gave the transfer company the final videos at 720p59.94 as well as our stock footage to upconvert to 1080i60.

Is that the best way to go? I am starting to think not due to the duplicate frames when you go from 30 to 59.94.

Alternatives would be to:

a) shoot and edit in 720p24
b) shoot in 720p24 or 720p30 and upconvert and edit the footage at 1080i60 through the kona... which would save us alot of money as we dont have to pay someone to transfer our tapes to 1080i, rather just give the client a harddrive full of the 1080i raw footage.

Any suggestions?

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Ramona Howard
Re: 720p30 through the kona?
on Mar 28, 2008 at 4:42:40 pm


This sounds more like a software issue as we can capture Varicam 720p59.94 both with or without the flagged frames using the AJA hardware. This is via SDI, so I would give that a try.


RaveHD is a Linux based solution using the AJA hardware. SpectSoft has written the Linux driver for the AJA hardware and all libraries that go into RaveHD.

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Jeremy Garchow
Re: 720p30 through the kona?
on Mar 28, 2008 at 9:29:51 pm

Simply duplicate the 720p24 Varicam settings and change the frame rate to 30.

It's easy and works.


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