720P/25P versus 720P/25PN

[steadicamsteel]

Well having never had to worry about "pull down" in the past therfor never took any real notice of it can someone explain why the PAL HVX-200 now has a 720P/25P (with 2:2 pull down), what would you use this setting for? and why not just shoot in the 720P/25PN (native) format?

Look forward to your responses.

Regards

Rich

[Aaron Koolen]

I don't think you can stream the non-Native(?) format (The one that's 25p embedded in 50i) over Firewire, so if you want that feature you have no choice.

[Anders Holck]

Yes when shooting to P2 you would use 25pn. as this gives you 2x the duration.

25p (with 2:2 pulldown) is there to comply with the streamformat.

In 720, 25p and 50p will stream, 25pn will not.

[Aaron Koolen]

Anders, are you sure you get twice the duration? I thought that 25p in a 50i stream was simply the two progressive fields placed into the interlaced fields at 50i, and therefore no extra space.

[Anders Holck]

720/25p records every frame twice in an 720/50p stream at 100mbps.

720/25pn records every frame once as a 720/25p file at 50mbps.

There are no fields in 720p.

So 25pn gets you 16 minutes per 8 GB, 25p is 8 minutes.

[Barry_Green]

720/25pN will give you twice the recording time of 720/25P mode or 720/50P mode.

720/25P gives you the look of 25p in a mode that can be streamed out the firewire port.

[Barry_Green]

DOH! Anders beat me to it.

[Aaron Koolen]

Thanks for that Anders. I was thinking that it was like the SD DVX100b where the 25 is interleaved in the 50i.

Man I wish I could afford one of those puppies ;)

[Anders Holck]

1080/25p works that way. It records every captured progressive frame as two fields in the 1080/50i stream.

Sony would call this 1080/25psf: Real 25p capture, but with the transport and recording of every frame in two halves.