1080p24 vs. 1080psf24

[Shane Ross]

I output 1080psf to HDCAM and D5 for my HD deliverables. AFAIK, it is true 1080p, not interlaced.

But what do I know…the land of HD is a complex field.

Shane

FCP Preferences set to UNCONTROLLED ADVICE
Littlefrog Post
http://www.lfhd.net

[Arnie Schlissel]

You may want to check with an engineer at your lab, but as I understand it, in 1080 there are no truly progressive tape or broadcast formats. So the 24psf format is just a simple workaround to deliver a progressive frame within an interlaced format.

Arnie
Now in post: Peristroika, a film by Slava Tsukerman
https://www.arniepix.com/blog

[Tony Manolikakis]

PsF is a Sony convention for progressive segmented frame. A progressive image is divided in a similar way to an interlaced image so that any device connected to the output will believe that it is looking at interlaced material, which at time this was developed, was required in order to fit in to the infrastructure of all facilities, think of switchers and monitors in particular. The image is completely progressive, is recorded to tape as progressive, and should be treated as progressive, there are no fields nor interlacing artefacts. The only time PsF matters is in transport into and out of the system or deck etc. Any system that supports 24p, supports PsF at it’s input and output (at the HD-SDI or YCbCr level). You should have nothing to worry about wrt this.

Tony
Rev13Films

[Gary Adcock]

[David Jahns] “I understand that it’s technically interlaced, but looks progressive. So, how does that work with the various HD decks & formats? HDCAM, D5-HD, and HDCAM-SR all say they do 1080p24 – do they also do 1080psf24?”

David – you have a good start here, first you understand that P and PsF are different, and while the NLE’s see the PsF format as progressive they play it back as 48i. Truly progressive playback of Psf can be accomplished with either the D5 or SRW (but not a “plain” HDCam deck)

[Shane Ross] “I output 1080psf to HDCAM and D5 for my HD deliverables. AFAIK, it is true 1080p, not interlaced.”
Shane brings up one of the “issues” while he is sending PsF to the deck- these mastering decks have the ability to convert between “true P” and PsF by using the setting controls on each of these 2 decks.

[Arniepix] “in 1080 there are no truly progressive tape or broadcast formats. So the 24psf format is just a simple workaround to deliver a progressive frame within an interlaced format.”

Partially true- there are true progressive frames in 1080, and Genesis, Viper, Vision Research all can generate true progressive content to Deck or DDR (like RAVEHD).
It has always been my understanding that Sony created the PsF format just so facilities could maintain legacy tape formats with the HDcam series decks, most of which can playback Beta tapes without issue.

Film based workflows are working with a DPX or Cineon formated sequence of still frames, so even though you appear to be working in Video, the application (AJA’s DPX to QT converter for example) has created a QT Ref movie of the stills to simplify the playback. So the video format is “almost” irrelevant.

Lastly, fewer and fewer productions working in a “true” 24.0 timebase, a film carryover, most now ease the DI process by staying at 23.98 for the post, Audio sync and for the ability to do realtime conversion to NTSC for approvals and monitoring.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows