24p vs 24Pf

[Kevin Lewis]

There is lots of info on this subject but nothing I found is giving me clear clarification. With the C100 is there any advantage to shooting 24pf instead of 24p if the final product will be delivered on DVD? Also does the answer change if i'm delivering on Blue Ray? When should I use one over the other?

[Walter Brokx]

Hmmm, good question.

Maybe in 24pF the rendering of the DVD is faster as a 3-2-pull down 60i version doesn't have to be interpolated?

[Gary Huff]

You should never shoot 24PF for any reason.

[Josh Bass]

Why do you say that?

[Gary Huff]

Originally Posted by Josh Bass

Why do you say that?

There is no possible scenario in which you need to shoot 24p with 3:2 pulldown in 60i. And to get the interlacing out of it, you HAVE to do a pulldown removal, and too many people don't know how to do this and end up de-interlacing, which HALVES your resolution.

[Josh Bass]

So is 24psf like the old 24p (or maybe im mixing it ip with advanced mode) on a dvx? The one meant to be used in a 29.97 timeline? If so, one could argue that a reason to use it is if you know youll be integrating with 60i material.

[Gary Huff]

Originally Posted by Josh Bass

If so, one could argue that a reason to use it is if you know youll be integrating with 60i material.

That's not actually a reason. First, you're going to have an overriding sequence setting, either 24p or 60i. Regardless of where you start, you'll end up either exporting 24p or 60i, and your NLE will take care of that for you. And since you are the one shooting, if you're ultimately going to 60i, then shoot in 60i, not 24PF.

Second, as has been stated before, the 99% likely scenario is that you are mastering 1080p24 for the web, in which case there is simply too much de-interlacing of improperly shot 24PF when it should have a pulldown removal process applied, which, currently, is pretty much only done in CinemaTools from Final Cut Studio 2/3 and After Effects.

There are too many C100 videos that look like crap because they were shot 24PF and improperly handled in post.

Just don't do it.

[Josh Bass]

Cool beans.

[Kevin Lewis]

Gary, does this also apply to the 30"pf" mode on the c100 or is it only applicable to 24pf? Can I assume that shooting 30pf is the basically the same as 30p?. From what I can tell, the only difference between the 30f and 30pf, is that I have to change the properties of the file from interpaced to progressive in Sony Vegas Pro.

[Rainer Listing]

If I can just step in ahead of Gary - who is totally correct - 30pf is theoretically the same as 30p and all you should need to do is tell Vega it's progressive. But in practice I don't think it works that way. Somehow Vegas seems to mess up HD psf footage. You can easily try it yourself - shoot a few clips of some fast action psf footage and have a look at it. I think it's a problem in Vegas. There's likely to be something weird going on with the cadence - not every clip. Doesn't seem to happen with PP, but easiest is never to shoot psf footage. Can't recall that this was an issue with my old XL2, which also stored psf.

[Gary Huff]

Unfortunately 30PF is the only option for 30p on the C100. I have expressed to Canon reps that a firmware update is sorely needed to remove both PF options from the camera and allow only 24p, 30p, and 60i (and while they are at it, there's no reason there can't be 720p60 either).

Both 24PF and 30PF are "true" 23.976 progressive and 29.97 progressive, it's just that the frames are blended into a 60i stream and must be "decoded" as such, and that's where pulldown removal comes into play.

For 24PF, you can get a pure 24p stream out of it, but it requires 3:2 pulldown removal, which is complicated because it involves picking the correct cycle for rebuilding the true frames. This is why the application support for it is limited (CinemaTools or After Effects). I accidentally shot one project in that mode when I first got my hands on the camera and processed all the footage in AE to remove the pulldown.

30PF utliizes 2:2 pulldown, which is much easier to deal with. All NLEs can do it, though some have trouble detecting that the C100 30PF mode is actually progressive. Because of this, I always use ClipWrap (on OSX) with internal C100 recording as it will correctly remove the 2:2 pulldown and leave the AVCHD format intact (and make individual .MOV files).

Ideally, just shoot to an Atomos device (Ninja-2/Blade/Shogun) and you can set it to automatically remove the pulldown while recording so that you have a pure 24p and 30p video file (out of the HDMI port, all footage is wrapped in 60i).

[Matt Davis]

So, with a bit of head scratching, brow furrowing... C100 specific:

24P - puts 24 frames per second (actually 23.97fps but never mind) down to the SDHC card using AVCHD in true progressive mode with no confusion by most NLEs over the 'interlaced' thing (though IIRC, I still had to do that in FCPX). No tears at bedtime.

24PF - puts 24 frames per second into a 60i stream, 60i is HDMI friendly, so if 24p is recording to a NInja or Pix, you want 24PF... But heaven help you if you want to put 24PF AVCHD onto a timeline, unless you do the 3:2 pulldown removal in something like Compressor whilst converting to ProRes. Erm, yes?

24P for AVCHD users, PF24 for Ninja users. Pix users are a special case.

Either way, it's all 23.97fps really (sending most readers scampering for the trees).

If anyone would like a Compressor droplet to convert C100 24PF AVCHD to 24P ProRes (actually 23.97), just shout. Sigh.

[Gary Huff]

Originally Posted by Matt Davis

24P - puts 24 frames per second (actually 23.97fps but never mind) down to the SDHC card using AVCHD in true progressive mode with no confusion by most NLEs over the 'interlaced' thing (though IIRC, I still had to do that in FCPX). No tears at bedtime.

Yes, purely progressive signal, no interlacing at all in 24P mode.

24PF - puts 24 frames per second into a 60i stream, 60i is HDMI friendly, so if 24p is recording to a NInja or Pix, you want 24PF.

Not necessary. I never shoot PF24 and I almost always use a Ninja Blade. No matter what setting you pick, 60i is *always* going out of the HDMI port (for compatibility with monitors and it's possible DigicDV III cannot process a SDI/HDMI PSF signal to send out as the C300 does exactly this as well with both SDI and HDMI).

If you leave the camera set to 24P, then you get true progressive 23.976 AVCHD and the Ninja will perform on-the-fly 3:2 pulldown to give you true progressive ProRes.

But heaven help you if you want to put 24PF AVCHD onto a timeline, unless you do the 3:2 pulldown removal in something like Compressor whilst converting to ProRes. Erm, yes?

Exactly that. Apparently Compressor 4 can also remove pulldown, but I don't think that was the case originally. Should work now, but it does require a transcode, which I try to avoid.

24P for AVCHD users, PF24 for Ninja users. Pix users are a special case.

24P for everyone. Never ever shoot PF24, there is no reason to. Both the Pix and the Ninja Blade do on-the-fly 3:2 pulldown removal, so the setup is exactly the same.

Set your frame rate to 24P, set Pix and Ninja Blade to 1080p23.976. Blade is automatic, Pix may require an extra step to initiate 3:2 pulldown, but that's all you need.

[Matt Davis]

Hmm - interesting about the Ninja Blade and P24.

When I checked the Blade with P24 off the C100, I waited a good 2 minutes to get a lock, and it didn't (even with that patient 'slow waggle') and a few times the Blade just locked up. 'Fine' I thought. 'It does intelligent 3:2 pulldown, what's it like with PF24?' Locks up in 10 seconds.

Sure, the AVCHD 'backup' footage was going to be a bit of a pain if I needed it, but I didn't want my primary source blinking out of record during a take (memories of the first Ninja units and my primary reason for buying a Pix).

So, if I need 24p at 4:2:2, I've used PF24 as it's been a quick and reliable lock from the Ninja, a bit of a PITA if I ever had to go with AVCHD, but I'd live with that rather than the risk of a dropped record.

But on your recommendation, I've persevered with P24 on the Ninja, and although it took 2 mins for it to not blink out, it's been going steadily for 20 mins now. I think, TBH, if I were in a hurry, I'd still look at 24PF for the Ninja and probably the Star (I don't own a star yet, but would be testing for speed and reliability of lock with both modes). My vote goes for the fastest and most reliable signal for an Atomos product to latch onto. :-)

[Gary Huff]

Originally Posted by Matt Davis

But on your recommendation, I've persevered with P24 on the Ninja, and although it took 2 mins for it to not blink out, it's been going steadily for 20 mins now. I think, TBH, if I were in a hurry, I'd still look at 24PF for the Ninja and probably the Star (I don't own a star yet, but would be testing for speed and reliability of lock with both modes).

Then something is wrong, either with your HDMI connection, your media, or you haven't updated the firmware of your Blade.

I never set PF24. I shot 24P in camera, the Blade locks into the 3:2 cadence nearly instantaneously and I don't have issues with it blinking out.

I have the Star and it works exactly the same way.