HD1400 24p Capture Interesting Question

[Walter Biscardi]

[MixTracks] “But, there was some over crank stuff on the tape running at a full 60 (no flags) that played faster on the NTSC timeline. That finding actually does not confirm what I thought, there should of been no difference on the 24p or 60 stuff on the tape.

So…. I am asking if the end result of the two methods below are the same, or did I need to do it the first way?”

If you have a mix of 24fps material and 60fps material on the same tape and you capture it all at at 24fps, then really the 60 material should play in slo mo in a 24 timeline. if your final output is 29.97 NTSC, forget about capturing 24, just capture everything at 59.94 since that matches the 29.97 final output. makes everything easy to work with.

If you have some material designed to play off speed, you can always remove the flagged frames and create self contained movies of those for insertion into your timeline. Or simply capture those correctly to make them off speed on the way in.

Walter Biscardi, Jr.
https://www.biscardicreative.com
HD Editorial & Animation for Food Network’s “Good Eats”
HD Editorial for “Assignment Earth”

“I reject your reality and substitute my own!” – Adam Savage, Mythbusters

[Bryan Arnold]

Agreed about the off-speed stuff, but, you say just capture everything at 60 because that matches the NTSC output, but the client wants the “24p look”. If I just captured everything at 60 then wouldn’t that negate the 24p look?

Since the camera always records at 60 anyway, I would need to only capture the flagged frames to get the 24p output.

So, leaving out the off speed stuff, the client asked my why I didn’t just capture the footage off the deck via the SD SDI output, that way it was allready NTSC, to save time. I said that I had to capture it at 24 then convert it because that was the only way we could get converted 24p off the tape, is this correct? I thought the deck did not read flagged frames, and always spit out 60, and to get any other frame rate you needed a way to pull the flagged frames. Unless the deck does in fact read and convert 24p to NTSC out of its SD SDI output.

[Walter Biscardi]

[MixTracks] “If I just captured everything at 60 then wouldn’t that negate the 24p look?”

Nope, the look is still there because the camera was in 24 mode.

[MixTracks] “So, leaving out the off speed stuff, the client asked my why I didn’t just capture the footage off the deck via the SD SDI output, that way it was allready NTSC, to save time.”

That would make it easy if you’re never going to deliver an HD master.

[MixTracks] “I said that I had to capture it at 24 then convert it because that was the only way we could get converted 24p off the tape, is this correct?”

If you absolutely positively want to edit in a 24p timeline, then you do need to convert or capture at 24. You can either capture DVCPro HD 60 via Firewire or SDI and then use the Frame Rate Converter to bring in everything to 24. Or capture DVCPro HD 24 via Firewire or if you have a Kona, bring it in via HD-SDI. I’ve found no quality difference between SDI and Firewire for DVCPro HD.

[MixTracks] “I thought the deck did not read flagged frames, and always spit out 60, and to get any other frame rate you needed a way to pull the flagged frames.”

The deck does read the frames and can record the 24p information from a camera using HD-SDI input as long as the User Bits are turned on. But the deck doesn’t need to read the frames when capturing, your system does. FCP does read the flags off the deck and a Kona system will read the flags too.

Walter Biscardi, Jr.
https://www.biscardicreative.com
HD Editorial & Animation for Food Network’s “Good Eats”
HD Editorial for “Assignment Earth”

“I reject your reality and substitute my own!” – Adam Savage, Mythbusters

[Bryan Arnold]

Walter: “Nope, the look is still there because the camera was in 24 mode.”

So the deck knows, and converts, 24p from the tape to NTSC?

Walter: “But the deck doesn’t need to read the frames when capturing, your system does.”

Is this statement conflicting with the first one?

Thank you so much for your help on this Walter.

[Walter Biscardi]

[MixTracks] “Walter: “Nope, the look is still there because the camera was in 24 mode.”

So the deck knows, and converts, 24p from the tape to NTSC?

Walter: “But the deck doesn’t need to read the frames when capturing, your system does.”

Is this statement conflicting with the first one?

Thank you so much for your help on this Walter.”

Have you done any test captures yet? You won’t understand anything I’m saying unless you have a deck in front of you and do some captures.

Walter Biscardi, Jr.
https://www.biscardicreative.com
HD Editorial & Animation for Food Network’s “Good Eats”
HD Editorial for “Assignment Earth”

“I reject your reality and substitute my own!” – Adam Savage, Mythbusters

[Bryan Arnold]

Yes, I did 2 tests…

1) Capture everyting out of the SD SDI on a NTSC timeline.

2) Capture everyting out of the HD SDI on a Varicam 24p timeline, then converting that to NTSC via the Kona2 SD SDI output to DigiBeta.

They both looked the same, and that was what you were saying also, I think. I thought that they would look different, and mabye they did and I could not notice it. The Panasonic dealer said up and down that I had to do number 2 above to achieve my result, but I now have to tell him differently, they are identical.

[Mike Most — account bouncing, bad address]

There is no conversion. There is no such thing as 720/24p video. The DVCProHD tape format is 60p all the time, regardless of what you’re feeding into it. The footage is padded with 3:2 pulldown for 24p, and other pulldown patterns for other frame rates (and the additional frames flagged for automatic removal when desired) before it’s recorded. That way the recorder can stay at a constant 60p.

The deck can use the frame flags to interpret the pulldown and output in different formats, depending on the option cards you have installed in it. If you have the HD-SDI option and can supply proper sync, it can output as 1080/60i or 1080/24p directly if you recorded with the camera in 24p mode.

[Bryan Arnold]

Thanks for the reply.

Really what this boils down to is, does the 1400 deck properly convert 24p flagged material to NTSC while still retaining that “24p look”.

I think we determined that the answer to the above is yes.

[Jeremy Garchow]

Yes! You have answered your own question when you said the captures look identical (save one is HD and one is SD). No matter what the signal that is coming out of that deck be it in HD or SD, is based on a 60 cycle stream. HD works in 59.94 frames per second, SD works in 59.94 fields per second (or 29.97 frames per second). The 24p look will be maintained no matter what resolution you capture in as long as the camera was in 24p mode.

Jeremy

[Gary Adcock]

[MixTracks] “Really what this boils down to is, does the 1400 deck properly convert 24p flagged material to NTSC while still retaining that “24p look”.”

Ok
if you show 24p material – the look is integral to shooting at 24fps, when the deck down converts the video stream to 29.97 NTSC ( there is no 24fps in NTSC it has to be 29.97) from the 59.94 720p video stream.
— where one progressive frame becomes 1 field of the NTSC interlaced signal.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows