Capturing 1080/25p HDCAM

[Jack Kelly]

“ARRGGHHH- it cannot possibly be “true progressive” if it is captured or played back with any kind of fields. ”

Maybe you’re aware of a definition of “true progressive” that I don’t know about. I count something as “progressive scan” if 2 things are true: 1) that the sensor captures whole frames at a time and 2) that I can see those whole frames when I get the footage back to my grading system.

25p over 50i satisfies my definition of “progressive scan” because my camera captures full frames, dumps those full frames to tape as two fields and I can then re-create the full progressive-scan image on my grading system by simply merging the two fields into a single frame. The camera’s sensor and the images which come out the back of my workflow are entirely progressive scan. It just so happens that the tape in the camera is recording a 50i signal; completely unaware of the fact that the two fields were taken at exactly the same moment in time. But the sensor is capturing progressive scan and my finished product is progressive scan.

https://en.wikipedia.org/wiki/Progressive_segmented_Frame

“With PsF, a progressive frame is sliced into two “segments”, with the odd lines in one segment and the even lines in the other segment. This allows for a progressive picture to be processed through the same electronic circuitry that is used to store, process and route interlaced video. Technically, progressive segments are equivalent to interlaced fields, but unlike native interlaced video, there is no motion between the two fields that make up the video frame, both fields represent the same instant in time.

… PsF has been recognized by Recommendation ITU-R BT.709 as a legitimate way to transport progressive frames within an interlaced system.”

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Jack Kelly
London
Dir / Prod / Camera
Jack-Kelly.com – my homepage
====================

[Jack Kelly]

Hi Gary,

Sorry, I’ve just re-read the entire thread (I should have done that before replying!) and I realise that you’re the one who taught me the definition of PsF in the first place! Sorry, I think I’ve just confused matters by replying! My apologies!

====================
Jack Kelly
London
Dir / Prod / Camera
Jack-Kelly.com – my homepage
====================

[Gary Adcock]

[Jack Kelly] “Sorry, I’ve just re-read the entire thread (I should have done that before replying!) and I realise that you’re the one who taught me the definition of PsF in the first place! Sorry, I think I’ve just confused matters by replying! My apologies! “

No harm…

and thank you for the apology.

gary

[Michael Ward]

Just thought I would say that Decklink HD extreme works perfect,
the images look stunning. Not only that, with the money I saved
on not buying a Kona card (AJA) I can now buy a Scarlet (4K)
brain), as I was I few thousand short. Would be a nice
set up, the Kona card, but Decklink is a powerhouse,
and flexible at that (It’s vertually a breakout box as well,
and it will take me ten years to figure out all the external
plug in features).

Michael Ward

Television Producer, C31

[Gary Adcock]

[Michael Ward] ” Michael Ward Television Producer, C31″

Michael- what does you post have to do with P vs PsF on a Sony EX1?

As a courtesy, I will keep my comment about the rest of your post brief.

I have never worked with a TV producer that was worried about anything other than what something was going to cost.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php

[Michael Ward]

Hi Gary,

The point of this post is to testify that DeckLink does process a 25p signal
at an amazing quality, that does preserve gamma, and has very much
the P cine look (CineAlta look) about it.

If you watch the Vortex video on Mastering the Sony PMWEX1 there are
comparison shots between the “i” and “p” look of different footage.
The narrator on the video concludes that he uses the progressive mode
for nicer cine’ like images.

What I’m saying is, no mater how you slice the cake, the integrity of the image
is there. It’s better than straight 50i for sure.

The “P” quality is obvious.

Money, well making a community TV show for 3 years for no money was very difficult,
perhaps I do worry about the money side too much.

be kind Gary,

Mike

[Gary Adcock]

[Michael Ward] “be kind Gary, “

Michael.
I said the nicest thing I could to you after your post. I moderate multiple AJA forums and my views are fairly common here on the Cow, if you had taken the time to read this entire thread, you would have seen there no mention of post hardware at all. This thread was a discussion on the subtly of this quirky technological issue from the camera side that many people are not aware of. It was not ever a discussion on who’s toys were better or how much they cost. So IMHO you were picking a fight.

Go back and read what you wrote. Its all about AJA vs Decklink with a camera that is not yet shipping. You did not have one single word about the Sony’s EX1 nor did you mention anything the actual debate on P vs PsF. Your entire comment was directed at the cost difference between BMD and AJA as hardware competitors and not about the facts in this thread, you started talking about Scarlet.

Oh and since you do not own your scarlet yet I doubt seriously if you have ever worked thru an entire project in in 1080 True P- it is not anything you have ever used before. I am on the bleeding edge of this stuff and I had never run into any 1080 true P until I was trying to solve a issue for Vision Research on the Phantom HD camera about 4 years ago.

I will state this as fact.

Working in 1080 as a true progressive signal and not as progressive segmented frame is rare indeed in the post world for the most part or at least it was until RED started shipping about 18 months ago.
1080 P is hard to look at even for someone versed in looking at 24 frame playback, because instead of 48 slices per second ( PsF) like you get in film projection, you are only seeing the 24 actual frames and I can assure you that it is hard to watch..

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php

[Gary Adcock]

[Michael Ward] “The point of this post is to testify that DeckLink does process a 25p signal
at an amazing quality, that does preserve gamma, and has very much the P cine look (CineAlta look) about it. “

Michael, did you actually read any these posts?

Sony’s EX1 does not deliver or Output a true P signal.
READ THE SPECS.
That camera delivers PsF like all Sony cameras, therefor the standard delivery is “I” (and did I mention that I consult to Sony on the EX)

Your decklink card delivers PsF also, since that is the format the camera is shooting- I do not believe that any decklink card can output P from PsF content (but correct me if I am wrong)

Cameras may shoot as “P” but in post production it is PsF only .

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php

[Michael Ward]

Gary I’m just going off the Sony manual. My EX1 shoots 1080 25p, and
I don’t know if you know this, but there is a relationship between hardware
and software.

The Sony EX1 is derived from the CineAlta line, it has 12 Gamma
settings (6 Cine Gamma settings).

I can set my camera to 50i or to 25p.

Decklink does a nice job of capturing the “P” look, versus the camera’s 50i footage.

It takes me about 10 secs to upload and watch footage on my 1080p
monitor – I don’t know what that silly crack about not having my project finished
was all about, a bit silly really, I should say we don’t want to get personal.

Gee Gary, are you really saying you are the only person in Australia that
can detect true ‘p’ in a frame? I’ve got it right here in front of me?
If you own a pmwex1 you would know what I mean.

You can shot onto 8gig cards (like p2), and upload it in a jiffy, then
have it on a time line minutes after shooting. I can in fact
shoot 50i and 25p on the same card, and then plug my camera into my giant
50 inch plasma and detect the variation between the footage very easily.
I really don’t see why you can’t understand what I’m saying?

PMWEX1 comes close to Red footage – that’s the Gamma look I’m after, that’s the P finish.
Check out the net, there are loads of comparison test (some are so close!!)
It must be P if it competes with 4k.

I notice you seem to guard this thread Gary – that OK, I’ve never meet a media consultant
who wasn’t a little bit obsessive about things.

Anyway, you should read the thread subject titles. As threads evolve it’s good to use
the subject titles to keep track of the changing thread themes, so you can evolve
with the conversation (between two ideas, not one), not harp back to a ‘dead thread’.

Having trouble with any of your current projects Gary??

Mike

[Gary Adcock]

Michael
a couple of things, you might actually read the entire thread rather than just the titles and then you might possible understand a few of the concepts.

Sony’s output format for playback is PsF, The EX1 cannot output a true Progressive signal in any way shape or form, while the camera can capture progressive imagery the video playback is what is called progressive segmented frame according to the SMPTE.
Those rules do not change because you are working in PAL.

[Michael Ward] “I really don’t see why you can’t understand what I’m saying? “

I feel the same- you do not understand at all there is a huge difference between what is called P vs the format you are shooting and editing in which is PsF.

https://en.wikipedia.org/wiki/Progressive_segmented_Frame
https://digitalcontentproducer.com/shoot/video_progressive_need_know/

Progressive Segmented Frame ( 23.98fps)

Progressive segmented Frame (PsF) is a High Definition video format used to store progressive content on interlaced media. Each progressive frame is segmented into two interlaced fields without interfield motion, or “combing”..

Motion picture film cameras produce progressive images, usually at 24 frames per second. In order to display those images on NTSC television, whose framerate is 29.97 frames per second interlaced (59.94 fields per second), each frame must be split into alternating groups of 3 and 2 fields. This is known as 3:2 pulldown. Certain high definition tape formats, such as HDCAM allow frame rates other than 29.97. It is therefore possible, using PsF, to store “true” 24 frames per second progressive images without pulldown, which then play back at the original framerate. Thus the 24PsF and 23.976PsF (for compatibility with NTSC) formats were devised, which exist on tape as 48 (or 47.952) fields per second interlaced. When set up correctly, a progressive scan monitor will read these interlaced fields two at a time, and display each pair as a single progressive frame, temporally identical to the source. PsF content can also be played back on interlaced displays, but the image will flicker. Sony’s CineAlta series of cameras are capable of recording directly to 23.976PsF and 24PsF on HDCAM tape.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article “progressive-segmented-frame”.

FYI

I live in Chicago.
I consult to Sony on the EX products line.

gary adcock
Technical Chair for the NAB 2009 Director of Photography Track
https://www.nabshow.com/2009/education/directorPhotography.asp

Studio37
Post and Production Workflows
Chicago,IL 60612

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php