24p editing vs 30p editing pros and cons? (HV20 vs HV30)

[skulpt]

Hey guys and gals. I'm in love with what I've seen with the HV20, and think the image quality and feature set is great. One of the things that has drawn me in is the 24p, and learning that this is the standard used on TV and movies. But after reading the big workarounds needed for each clip to work with it, find an editiing solution that works with it, and removing pulldown, it's kind of scared me off a bit.

Will the new HV30 with a 30p mode solve some of that? What are the advantages of 30p mode on the HV30 compared to 24p for editing? What are the disadvantages?

Sorry if these are basic questions. I'm just wondering if it makes more sense for me to just wait a bit and get an HV30, despite the higher cost.

Brian

[Lunchbox]

24p is not the standard TV used. It's for film. NTSC broadcast at 30fps (29.97fps). So in order to show a film on TV, interpolated frames (pulldowns) are inserted to 24fps to form a 30fps video.

You can just edit your PF24 footage as 60i not a problem.

30p gives the kind of film look without having to deal with removing pulldowns.

[lordtangent]

Taky, I have to dis-agree with you on 24p not being a "TV" standard. "Single camera" style TV shows (that is to say the higher production value shows that play on prime time and are shot on film) are almost always shot, cut and conformed at 24fps. Only live "multi camera" shows, new and sports shot with video equipment are done at "video" frame rates (60i, 60p, etc) Actually, many multi camera "Sit-Coms" show are actully shot at 24fps also, using film cameras rather than video equipment.

Some commercials, music videos and other "special" projects are shot at 29.97p, to get a particular look. As you mentioned already, it provides a "filmic" look while matching the frame rate of video 1:1.

To answer skulpts question regarding 30p vs 24p

30p is a great way to get a film like look from your video. Using it with the HV30 will allow you to side step the difficulties of working in 24p with the HV20. That's a plus.

In some ways 24p is more flexible though. It's compatible with both "NTSC" and "PAL" frame rates by using either 3:2 pulldown or 1:1 pulldown (with a mild adjustment to play back rate to 25fps). A lot of modern HDTV stuff can also handle 24p natively at 24p. Really, for better or worse, 24p is the closest thing to a universal standard that exists these days. You would have a trickier time moving 30p to PAL frame rate system.

Honestly, if I coudl have waited for teh HV30, I would have. It'd be nice to have the option of 24p, 30p and 60i. They all have value. For example, with the HV30 you could shoot at 30p and then play it back at 24p to a get a mile slow motion effect very easily. And as meany people have been doing already with the HV20, you can shoot 60i and delace that to 60p... then play it back at 24fps gettting a really nice slow motion effect.

[Lunchbox]

In the United States or where NTSC is their standard TV broadcasting signal, video is broadcast at 29.97fps frame rate. That's the TV standard. Film is 24fps. To make film be able to broadcast in NTSC land, pulldowns are inserted to form the 29.97 frame rate. Undoubtedly 24p is NOT the TV standard.

A lot of the TV shows are shot with film, many sitcoms too. The telecine process is performed so that 24p film can be broadcast. From the frame below, you can see that's the pulldown frames insert to the film look in "The Office".

http://hottaky.com/hv20/office.jpg
http://hottaky.com/hv20/officePD.jpg

The TV shot was shot in film in 24p. But what you are watching on TV is indeed a 29.97 frame rate converted video. Thus, 24p is not a TV broadcast standard.

[Lunchbox]

... It's compatible with both "NTSC" and "PAL" frame rates by using either 3:2 pulldown or 1:1 pulldown (with a mild adjustment to play back rate to 25fps).

If I understand correctly, a 3:2 pulldown means for every 3 frames, 2 interpolated frames were generated in the telecine process. So a 24 fps video will be come a 30 fps video. I don't know what is 1:1 pulldown. If it's the same way, each one frame will have one interlated frame generated. The final video will be 48fps. It goes no where.


you can shoot 60i and delace that to 60p...

If you deinterlace 60i footage, you got a 30p video, bot 60p.

[Lunchbox]

I just did a test with Ppro using 30F footage.

(1) Slow down to 50%. Output 29.97fps (http://hottaky.com/hv20/50slomo.wmv)

(2) Slow down to 50%. Force output to 24fps (http://hottaky.com/hv20/24slomo.wmv)

(3) Interpret the 30fps footage as 24fps and remain 100% (http://hottaky.com/hv20/24force.wmv).

To me, (1) gives the best slomo output. (2) generate some ghosting frames because Premiere try to combine some frames into one in order to get rides of 6 frames each second. (3) although it looks nice but it is not slow enough. It is only 80% slower than real life.

[Ian-T]

I have always understood as a rule of thumb...never try to convert 30p to 24p. Also in programs like Vegas you can deinterlace 60i to 60p. My former cam was 30p..I like the motion of 24p better. I would rather have a cam that could shoot 60 full frames instead of converting 60 fields into 60p. This way I would have the best of both worlds...smooth slow motion and clean 24p if I wanted to....no resolution loss.

[StealthBeagle]

A lot of the TV shows are shot with film, many sitcoms too. The telecine process is performed so that 24p film can be broadcast. From the frame below, you can see that's the pulldown frames insert to the film look in "The Office".

The TV shot was shot in film in 24p. But what you are watching on TV is indeed a 29.97 frame rate converted video. Thus, 24p is not a TV broadcast standard.

This is incorrect. "The Office" shoots on high def video (not film), according to the bonus features on their DVDs.

[2Bdecided]

If I understand correctly, a 3:2 pulldown means for every 3 frames, 2 interpolated frames were generated in the telecine process.The output is not frame-based, and it's never interpolated. It is field based, and where there are extra fields it's a simple repeat of a previous field. There are plenty of links which explain how it works. There is no magic at all.

Your frame capture looks blurred because you're combining two different fields which originally came from different source frames. Of course you should never combine fields like this*, and a real TV would never do so.


If you deinterlace 60i footage, you got a 30p video, bot 60p.You can get either. Some people call 60i>30p deinterlacing, while they call 60i>60p bobbing. I don't find that differentiation useful, since today most good "deinterlacers" or "bobbers" let you select the output rate - 60p = keep temporal resolution (double frame rate) or 30p = half temporal resolution (same frame rate).

Cheers,
David.

P.S. * - we do in PAL land, but you NTSC folks don't have that luxury, except for 30p-in-60i content which can be displayed correctly just by showing each frame, just like our 25p-in-50i content.

[skulpt]

So basically, a 60p 1080 native capture is the holy grail of HD capture then, right? What cams can do this now, and how much do they cost? (I know they are wayyyy beyond this price range though). In other words, how long do you guys/gals think before we see say an HV60 around this price range that can do native 60p HD?

Are we just using a stopgap HD spec until the real HD capture comes to cams around this price range?

Brian

[Lunchbox]

The output is not frame-based, and it's never interpolated. It is field based, and where there are extra fields it's a simple repeat of a previous field. There are plenty of links which explain how it works. There is no magic at all.

By interpolate, I mean the new frames generated are mixing fields from the Previous frame and Next frame.



Your frame capture looks blurred because you're combining two different fields which originally came from different source frames. Of course you should never combine fields like this*, and a real TV would never do so.

The TV captured frame is from a media playback program. I didn't do anything to combine any fields. It's just a pause in the playback program. That particular blury frame shows pulldown is inserted to the original stream.

[Ian-T]

So basically, a 60p 1080 native capture is the holy grail of HD capture then, right? What cams can do this now, and how much do they cost? (I know they are wayyyy beyond this price range though). In other words, how long do you guys/gals think before we see say an HV60 around this price range that can do native 60p HD?

Are we just using a stopgap HD spec until the real HD capture comes to cams around this price range?

BrianThe new DSLR camera by casio I believe does 60fps...it is a CMSO chip.

[lordtangent]

In the United States or where NTSC is their standard TV broadcasting signal, video is broadcast at 29.97fps frame rate. That's the TV standard. Film is 24fps. To make film be able to broadcast in NTSC land, pulldowns are inserted to form the 29.97 frame rate. Undoubtedly 24p is NOT the TV standard.


You have a very good point and after re-reading your post I realized I kind of took a leap of logic from what you actually said.

But to connect it back to the point of MY post. While "24p" isn't currently a broadcast standard, my point was to illustrate that 24fps (actually 23.976) is still a very common frame rate in TV land. It's really not exotic at all and is used all the time. And nowadays with 24pHD, even posting in 24p video isn't an exotic thing to do. In fact, it's quite the norm.

And for those thinking that 60p is the Holy Grail of frame rates, I suggest you do your math again. A CLEAN 24p can never be extracted from 60fps. (there is be judder as there is still a temporal disparity between the two) 120fps is actually the lowest common denominator. But the problem there is that if you used that frame rate you would never be able to get a pleasingly slow enough shutter speed to make the 24p look good, even if you used a 360deg shutter angle. (1/120th of a sec) 120fps decimated to 24fps would be really stroby.

[Lunchbox]

Yeah I see your point. 24p frame rate is common because of film. 24fps is not a TV broadcast standard. It was made common in TV broadcast because of the telecine process to make it 30fps.

With respect, I wouldn't think 24p on TV is a norm. Only limited number of HDTV and limited number of DVD/HD/BD players are capable of true 24p display.

Regarding the 120fps as common denomintor, where you hear that from?

[Dota]

Hey guys, how do you convert 24p to 30 by inserting pulldowns? Which program can do that and is it an automatic process?

[Lunchbox]

You can use program like After Effects to insert pulldown.

[David Newman]

Let me jump in on this debate.

30p is certainly the easiest to capture and edit to maintain a progressive image, that sound good. 24p for course requires the pulldown to be removed first, but otherwise it is the same workflow. The difference comes when mastering, either 24 or 30 works fine for web preventation, but 24p is better for most other distribution formats.

BluRay -- doesn't have a 30p profile, only 24p and 60i. Of course 30p can be encoded as 60i, however interlace presentation has to flicker issues if the source vertical bandwidth is too high. 30p to 60i can cause twittering (inter-line flicker) when a display converts 60i to 60p for HD display (most displays aren't expecting 30p over 60i sources, so they do the interpolation wrong.) This is not a big issue for HV30s, which are a little softer at 1080p, but people are have issues with the 30p mode from Sony EX1s out to BlurRay, when the 24p works fine. Bascially most modern display can do 2-3 pulldown reconstruction, but not all do 2-2 (30p in 60i) pulldown detection, mainly because 2-2 sources are rare in professional sources.

DVD -- doesn't have either 24p or 30p profiles, only 60i, but all progressive DVD player can remove 2-3 pulldown, but not all 2-2, so same issues as BluRay. So 24p looks go on progressive displays, yet the 30p experience is varied. CRT display is fine for both, it the move to 60p progressive displays that is the issue.

Note: 24p on DVD/BluRay, pulldown is added automatically by the authoring sotware, you don't want to add pulldown manually with After Effects or elsewhere as the authoring software will like encode the image as regular 60i source (20% less efficient = lower quality) and not set the repeat flags -- many progressive DVD players use the repeat flags to extract pulldown. 30p on DVD has no repeat flags, making progressive detection more difficult.

Bonus, 24p can be easy converted to 25p/50i PAL very easily, whereas 30p to 25p/50i is a total pain. Same for 25p to 24p, easy.

[Rumpelgeist]

I wonder how they record and display 25p in 50Hz systems. I am sure they do it correctly, why cannot they do it for 30p? Anyway, I've got the OPPO player because it can remove 2-2 for DVDs. I've got the the Samsung Blu-ray BD-P1200 player, because its HQV chip can remove 2-2 for SD and hopefuly for HD (I don't have the HD HQV test disk).

Aside, those who spec'd Blu-ray were idiots to not include 30p. HD DVD supports 30p directly.

[David Newman]

I wonder how they record and display 25p in 50Hz systems. I am sure they do it correctly, why cannot they do it for 30p? Anyway, I've got the OPPO player because it can remove 2-2 for DVDs. I've got the the Samsung Blu-ray BD-P1200 player, because its HQV chip can remove 2-2 for SD and hopefuly for HD (I don't have the HD HQV test disk).

2-2 pulldown, I have a 60p OPPO player for the same reason. I'm not sure how native 25p players do it, all I know it NTSC players mostly do it wrong.

[Lyris]

Sadly, most PAL players don't get 2-2 Pulldown Detection right either (a real shame given that it's needed for the best playback of PAL movies!). I actually helped Oppo refine the firmware in their DV-980H to get that to work.

[David Newman]

That's pretty cool, I love my DV-981HD.

[Rumpelgeist]

Sadly, most PAL players don't get 2-2 Pulldown Detection right either (a real shame given that it's needed for the best playback of PAL movies!). I actually helped Oppo refine the firmware in their DV-980H to get that to work.
Could you tell more about that?

[Lyris]

About the pulldown detection or my assisting them? Oh hell, here's both for anyone reading...

A 2-2 film cadence has been typically tricky for video processors to detect. Whilst 2-2 means that both fields are the same, the processor in a DVD player will assume the content is Video that needs deinterlaced, unless it knows better. So it'll start interpolating between fields and creating jaggies, when it doesn't need to.

Typically it's the more advanced processors that can detect 2-2 cadence and treat it properly. The Oppo 980H doesn't have such a processor and relies on a single chip from Mediatek for MPEG decoding, system control, and video processing. Keeping things on a single chip has advantages and disadvantages (the Genesis/Faroudja FLI2300 chip inside the Oppo DV-981HD has some nasty problems of its own which affect the picture).

Now, I write hardware reviews for DVDTimes.co.uk (and HDTVtest.co.uk) and Oppo asked if I'd be interested in reviewing the 980H. Since we're a UK site and our SD DVD content is in PAL (25fps) format, I told Oppo that I'd only be interested in reviewing it if it would compensate for 2-2 properly. Almost all single-chip (cheap!) DVD players do not do this properly: yes, the majority of Progressive Scan DVD players can't convert European DVDs to Progressive Scan format correctly.

Oppo got back to me and told me that 2-2 detection worked on the player, which shocked the living hell out of me. At first, it sort-of worked if the conditions were right (For example, at one point during firmware testing, we discovered it would only work if an NTSC 3-2 disc had been inserted beforehand, and even then it would only work for the top part of the screen!). But, I am also (most recently) a DVD author/encoder so was able to make and send Oppo and Mediatek test discs to really nail the problems.

I also asked Oppo if they would add a selectable deinterlacing mode (they did, if you look on the 980H, the option labeled "De-interlacing mode" was my idea/request). So if the user is watching 2-2 content, and the player isn't picking up on it, they can simply tell it how to best process the video.

Long story short, the player plays European 25p film content correctly now (in most cases). Oppo are so receptive and always get the most out of the hardware they have.


Hey guys, how do you convert 24p to 30 by inserting pulldowns? Which program can do that and is it an automatic process?If your delivery method is DVD, you can actually encode the disc as "24p" and the Pulldown will be applied by the DVD player as it plays back the disc (so that it can be viewed on a 60hz TV - a minority of DVD players can actually output this as native 24p to a 24p capable display). This is the method used by Hollywood for their DVD content.


That's pretty cool, I love my DV-981HD.I was a fan of that one too, although the FLI2300 chip in there can cause some odd artefacts when you use the upscaling feature. I actually caught a bug on that player too where the Noise Reduction feature would accidentally enable itself and cause smearing.

[2Bdecided]

DVD -- doesn't have either 24p or 30p profiles, only 60iWithout getting really complicated, it is possible to store 30p as is on a DVD - individual frames, no fields, no flags. This is exactly the same as for 25fps "PAL".

Cheers,
David.

[2Bdecided]

If your delivery method is DVD, you can actually encode the disc as "24p" and the Pulldown will be applied by the DVD player as it plays back the disc (so that it can be viewed on a 60hz TV - a minority of DVD players can actually output this as native 24p to a 24p capable display).This isn't quite right - you store 24 progressive frames per second, and include flags to repeat some of these fields (half-frames) to bump this up to 60i.

The flags are in the stream itself, and the output of a standard MPEG encoder from such a stream is 60i. You cannot put 24p without the flags onto a DVD.

DVD players which output 24p are ignoring the flags (or, more often, doing much clever things, since the flags aren't always correct or reliable - e.g. the encoder might add a repeat a field simply because nothing changed and this is an efficient way of encoding that field, not just because it's 24p!).

Cheers,
David.

[Rumpelgeist]

Good to know that DVD supports 30p as is. Once again I can't help cursing Sony for not including 30p into BD standard. Why, oh why?

[Tulak]

Good to know that DVD supports 30p as is. Once again I can't help cursing Sony for not including 30p into BD standard. Why, oh why?

HD DVD Supported 30P:hv20-smilie70:
Why Sony not included that is good point!:hv20-smilie102:

[lordtangent]

Regarding the 120fps as common denomintor, where you hear that from?

Math. The common denominator of 1/24 and 1/30 is 120.

If the goal is to find a temporal frequency where both 24fps and 30fps have a common cadence (no temporal offset as a result of simple frame dropping) then 120FPS is the only frame rate that works. (Though the results might still look stroby since you could not possibly shoot with anything longer than a 1/120th of s second shutter.)

Of course another side effect of shooting 120fps would be that you could make 60i or 60p material as well (And it would not seem too stroby since 1/120th of a second shutter is about right for a temporal sample rate of 60) You could also make great slow-mo.

[lordtangent]

Without getting really complicated, it is possible to store 30p as is on a DVD - individual frames, no fields, no flags. This is exactly the same as for 25fps "PAL".

Cheers,
David.

Yes, I can confirm this as I have done it myself. (30p... as well as 24p) I had to encode the video external to my authoring software in a stand-alone compressor. But it works fine and I noticed no twitter or other artifacts on playback.

[Tim_B]

30p gives the kind of film look without having to deal with removing pulldowns.


Quick question. Rookie here with a HV30 and Vegas Pro 8. I cant seem to find any info on editing 30p. You said no pull down is needed when shooting 30p. So when shooting 30p, I can just capture and edit at 29.970 and then render it at 29.970 as well? I don't need to do any of the 24p steps?

Thanks.

Tim

[Lunchbox]

That's correct.

btw, what is "rookie" ?

[Tim_B]

That's correct.

btw, what is "rookie" ?

rookie = newbie

Thank you.

[zcream]

So, in the end. Did anyone decide on a good way to take the 30P from say the 5D MArk II and convert it to 24P ??

[sonicballer8888]

You can use program like After Effects to insert pulldown.

Can't you just render your 24p footage as 30p?

it looks fine to me. I've tried it.

:hv20-smilie87:

P.S. I honestly don't understand why all this frame rate buzz is such a big deal. Couldn't you just render your 30p footage as 24p or 24p to 25p or 30p to 25p, etc.

But I do know that you cannot convert interlaced videos to progressive videos without deinterlacing. Good thing I have Vegas and AE though! :hv20-smilie03:

[Lunchbox]

Of course you can just render 24p to 30p. Then there will be 6 interpolated frames blended by adjucent frames per each second. The resulting video will be blury especially in motion scene.

[sonicballer8888]

Of course you can just render 24p to 30p. Then there will be 6 interpolated frames blended by adjucent frames per each second. The resulting video will be blury especially in motion scene.

That's what I thought.

So it would be better to manually add the frames in AE?

BTW http://videocopilot.net has a nice frame rate converter preset.

[Rumpelgeist]

But I do know that you cannot convert interlaced videos to progressive videos without deinterlacing.
Duh. By definition, deinterlacing is a process of converting interlaced video to progressive.

[Maxwell]

Some commercials, music videos and other "special" projects are shot at 29.97p, to get a particular look. As you mentioned already, it provides a "filmic" look while matching the frame rate of video 1:1.
30p is a great way to get a film like look from your video.

Wait, I always thought 24p was a way to get the film look thing?

[um3k]

There's far, far more to a film look than just the frame rate.