Why 24P is Important from RED Centre Podcast at DVinfo.net

Mark Holmes · June 1st, 2009, 08:17 PM

For those who don't understand the importance of 24P, and for a very in-depth discussion of its relevance in the 5D MKII (and a bit of a digression into the 5D's importance in the digital cinema world) head over to the RED Centre Podcast. The June 1st edition, Episode #36, about 9 minutes in, talks about the 5D Firmware Update and why 24P is important at about 15 minutes in.

RED Centre is a podcast put on by the crew at FX Phd., a training site/school for visual effects artists and deals specifically with the RED Digital Camera and more generally with digital cinema. It's worth subscribing to via iTunes... fascinating stuff for tech-heads.

RED Centre: fxguide - vfx knowledge

Peer Landa · June 1st, 2009, 09:18 PM

Quote:

Originally Posted by Mark Holmes

fascinating stuff for tech-heads.

Mark, many thanks for posting that link. Those guys remind me of a former professor I had Personal page in acoustics -- he could make the most dry & complicated stuff both entertaining and understandable. Had to crack up when they said something like "But of course, it's only nuts who listen to this anyway." (Obviously, they know their audience ;^)

-- peer

Mark Holmes · June 2nd, 2009, 01:18 PM

Thanks Peer, it is nice being a nut...

Evan Donn · June 2nd, 2009, 04:14 PM

It's a good explanation of why 24p is important for those planning to go to filmout, and why 30p is particularly ill suited for that purpose (or for converting to 24p) - but if that's not the plan (and it's probably not for most of the content shot on the 5D) I'm still not convinced of the absolute need for 24p.

30p IS NOT the news/reality/sports/video look that a lot of people seem to be making it out to be - 60i is (in the states at least). 30p is significantly closer to 24p than to 60i... it's a 25% increase in temporal resolution compared to a 250% increase! In terms of motion rendering I think the shutter speed has far more impact on the look than the difference between 24 & 30p - and now that we can control the shutter reliably I think it'll have a big impact on the look of stuff we see from the camera from here on out. I'd bet that most of the audience won't see the difference.

Edit: Also just wanted to say it's really worth listening to the rest of the podcast, the guest is really interesting, soldier/photographer/videographer talking about how the 5D is allowing them to shoot in low-light combat zones without having to use night vision cameras thanks to lenses like the 85mm 1.2.

Mark Holmes · June 2nd, 2009, 05:10 PM

Evan, it's not so much for the possibility of filmout that people are clamoring for 24P or 25P - it's for the problems that will come when a 30P project is ready for distribution to any PAL country - which is most of the world.

I'm dealing with this right now with our feature film, which was shot 24P, and distributed as such for the North American market, but every other territory we've dealt with is PAL. The conversion from 24P to 25P is not a huge headache, but is next to impossible when converting from 30P - at least with good results.

This is enough of a problem that it is keeping me from purchasing the 5D MKII or even using it on any project that has the possibility of any eventual distribution.

Of course, the 5D can be used for projects that will only see the internet, but that is extremely limiting... at least if you are trying to make a profit.

Jon Fairhurst · June 2nd, 2009, 05:43 PM

And then there's the web, where 24p takes less bandwidth than 30p. And specifically Vimeo, which throws away frames to achieve 24p.

Our older camera did 30p. We encoded 15p for the web, except for webisodes that had single frame gun flashes. If there wasn't much motion, 15p was fine.

Tony Tibbetts · June 2nd, 2009, 05:56 PM

Quote:

Originally Posted by Mark Holmes

The conversion from 24P to 25P is not a huge headache, but is next to impossible when converting from 30P - at least with good results.

Time consuming? Yes. Good results? Yes. Impossible? No.

Sofia's People: Canon 5dmk2 24p on Vimeo

Looks good to me.

Mark Holmes · June 2nd, 2009, 06:48 PM

Quote:

Originally Posted by Tony Tibbetts

Time consuming? Yes. Good results? Yes. Impossible? No.

Sofia's People: Canon 5dmk2 24p on Vimeo

Looks good to me.

Yes, of course it looks good to the naked eye, but a Quality Control Report on an HD-Cam PAL tape from a post-production house is LOOKING, often on a frame-by-frame basis, for problems such as ghosting, which are often the result of these kind of conversions.

It's not fun to be told that the tape you submitted to a distributor is not acceptable, after you have paid a post house over a $1,000 to produce the tape. And if your problem was caused by initial image acquisition in 30P, there is nothing you can do about it months later...

Jay Bloomfield · June 2nd, 2009, 07:24 PM

I don't want to instigate another tiring 24p "rant" thread, but other than the clean conversion to film, what is real advantage of 24p? Film has a certain color look to it, but that has nothing to do with frame rate. DOF has nothing to do with 24p, as evidenced by the 5D2. The only thing you get from 24p that is "filmic" is motion blur, because you have less frames per second.

Evan Donn · June 2nd, 2009, 07:36 PM

Quote:

Originally Posted by Mark Holmes

Evan, it's not so much for the possibility of filmout that people are clamoring for 24P or 25P - it's for the problems that will come when a 30P project is ready for distribution to any PAL country - which is most of the world.

Got it, that's what I was looking for - most people's justifications for needing 24p seem to just be 'film look', but international distribution issues make it a true, practical need. Well, let's hope Canon's really working on it.

Tony Tibbetts · June 2nd, 2009, 08:41 PM

Quote:

Originally Posted by Mark Holmes

Yes, of course it looks good to the naked eye, but a Quality Control Report on an HD-Cam PAL tape from a post-production house is LOOKING, often on a frame-by-frame basis, for problems such as ghosting, which are often the result of these kind of conversions.

Ghosting? I've seen ghosting in stuff that originated 24p and 25p. So is that footage unacceptable? Even if it started and ended up at the same exact frame rate? Seriously, if it looks good to the naked eye, then really, who's going to care? I doubt a post house would hold it's nose up in the air and refuse a paycheck based based solely on a few bits of ghosting?

A transfer to film requires an image sequence. 24 frames per second is still 24 frames per second no matter what the original frame rate was. If converted properly, if the cadence and timing is good, and if it looks good to the naked eye. What's the problem exactly?

Not trying to be argumentative, but I just not sure I see what the issue is. I could be wrong. It's just that your point seems a bit presumptive as to what the end result of a 30p-24p conversion would be.

In the past I admit it was rough going that route, but now it seems there are perfectly acceptable options for this.

The podcast is confusing. One minute these guys are discussing 30 frames per second and and the problems inherent in converting it, yet they relate it to interlaced fields. Huh? Last time I checked the 5D shoots 30p.

Maybe I'm missing something.

My point is that obviously you can deliver a fairly clean 24p project from 30p material. There are plenty of examples floating around the web. I'd bet money a post house isn't going to care that much if it's a clean conversion.

Mark Holmes · June 2nd, 2009, 09:00 PM

Ok, one last post and then I'll let it die.

Trust me. It matters.

The post house will still take the check, yes, of course. But when you distribute a film, you have to turn over a master to whoever is paying YOU. They, in turn, send your master to a post-production house or quality control firm, whose sole job is to go over the master with a fine-tooth comb, looking for flaws in both the video and audio. They are being paid by the distributor, say, Showtime, or ABC. They are covering their ass by finding flaws in the material. A 30P to 24P conversion can result in the kind of flaws that can lead them to rejecting your master.

That is very expensive.

But I'm sure you are aware of this; it simply bears repeating.

And look over the resumes of the guys who host the RED Centre Podcast. They know what they're talking about. Trust them.

Marcus Marchesseault · June 3rd, 2009, 12:04 AM

For all the Europeans on this board and any future Aussie or European customers of mine, I hope for 25/24p. I will still be shooting with the 5D regardless but I hope even more firmware upgrades happen. I just won't be infuriated with Canon from now on since I think I'll be very pleased when I shoot with exposure control. Now that I'm happy with them more completely, I hope for their sake they get 25p working so they can sell more cameras.

Robert Martens · June 3rd, 2009, 01:44 AM

Evan, you are not alone; this precise concern has been driving me absolutely insane for months now, what with the increased prevalence of video modes on still cameras of late. I was beginning to think I was the only one who thought about this.

The international compatibility issue I can completely understand. 24p can be converted to both NTSC and PAL rates without the headaches of the other potential cross-conversions, so it makes sense there. Combine that with the fact that the Blu-ray video standard only supports 24p and 60i, not to mention the concern for cost on film shoots, and the desire to shoot 24p makes perfect sense.

But, despite the many legitimate reasons you can come up with to support the 24p fever, the podcast hosts seem mostly concerned with the misconception Evan addresses in his post: confusing 30p with 60i. They say "thirty frames" when they should be discussing "sixty fields". The example they give, where audiences can tell commercials from movies, is not because the commercials were shot at thirty frames per second, but because they were shot at sixty fields per second.

One could technically say that they were shot at thirty frames per second, but in the context of interlaced video "frame" has a different meaning, and it's only a logical unit of information that itself we never get to see. Each of those frames contains two separate images which, though stored together, were captured, and are ultimately played back, one after the other, giving us sixty distinct points in time represented per second, in stark opposition to both 24 frame per second film and 30p video.

The video look that we (at least in the NTSC world) are conditioned to see as "home movies" instead of "cinema" does not come from a measly six additional images per second. It comes from the almost thirty-six extra samples of time you get when you shoot interlaced material in our parts of the world. It's two and a half times the motion sampling that stands out, not a paltry quarter-again addition.

Those more experienced individuals out there can more than likely spot the difference between 24 and 30 frames per second, if they're paying attention, but a real, honest-to-God thirty frames per second is not the plainly obvious smack in the face that makes even the least trained home viewer say "this doesn't look cinematic", and speaking purely for the look of the footage, doesn't make a significant difference.

Brian Luce · June 3rd, 2009, 02:50 AM

This is a great discussion but I'm voting two thumbs down on the podcast, it's filed with mindless chatter about stolen Red cameras and a lot of yourtaxdollaratwork GI Joe combat stories about winning the Silver Star etc. I didn't make it to the end, I couldn't take it. I caught about 90 seconds midway that had some interesting info re 24p but it's a lot of noise other than that.

The OP has a lot of good insight, I hope he revisits his thread. The podcast? ctl alt del.

June 1st, 2009, 08:17 PM	#1
Mark Holmes Regular Crew Join Date: Mar 2004 Location: San Diego, California Posts: 119	Why 24P is Important from RED Centre Podcast For those who don't understand the importance of 24P, and for a very in-depth discussion of its relevance in the 5D MKII (and a bit of a digression into the 5D's importance in the digital cinema world) head over to the RED Centre Podcast. The June 1st edition, Episode #36, about 9 minutes in, talks about the 5D Firmware Update and why 24P is important at about 15 minutes in. RED Centre is a podcast put on by the crew at FX Phd., a training site/school for visual effects artists and deals specifically with the RED Digital Camera and more generally with digital cinema. It's worth subscribing to via iTunes... fascinating stuff for tech-heads. RED Centre: fxguide - vfx knowledge __________________ Mark Holmes www.daisy3pictures.com

June 2nd, 2009, 04:14 PM	#4
Evan Donn Major Player Join Date: Feb 2006 Location: Philadelphia Posts: 795	It's a good explanation of why 24p is important for those planning to go to filmout, and why 30p is particularly ill suited for that purpose (or for converting to 24p) - but if that's not the plan (and it's probably not for most of the content shot on the 5D) I'm still not convinced of the absolute need for 24p. 30p IS NOT the news/reality/sports/video look that a lot of people seem to be making it out to be - 60i is (in the states at least). 30p is significantly closer to 24p than to 60i... it's a 25% increase in temporal resolution compared to a 250% increase! In terms of motion rendering I think the shutter speed has far more impact on the look than the difference between 24 & 30p - and now that we can control the shutter reliably I think it'll have a big impact on the look of stuff we see from the camera from here on out. I'd bet that most of the audience won't see the difference. Edit: Also just wanted to say it's really worth listening to the rest of the podcast, the guest is really interesting, soldier/photographer/videographer talking about how the 5D is allowing them to shoot in low-light combat zones without having to use night vision cameras thanks to lenses like the 85mm 1.2. __________________ My latest short documentary: "Four Pauls: Bring the Hat Back!"

June 2nd, 2009, 05:10 PM	#5
Mark Holmes Regular Crew Join Date: Mar 2004 Location: San Diego, California Posts: 119	Evan, it's not so much for the possibility of filmout that people are clamoring for 24P or 25P - it's for the problems that will come when a 30P project is ready for distribution to any PAL country - which is most of the world. I'm dealing with this right now with our feature film, which was shot 24P, and distributed as such for the North American market, but every other territory we've dealt with is PAL. The conversion from 24P to 25P is not a huge headache, but is next to impossible when converting from 30P - at least with good results. This is enough of a problem that it is keeping me from purchasing the 5D MKII or even using it on any project that has the possibility of any eventual distribution. Of course, the 5D can be used for projects that will only see the internet, but that is extremely limiting... at least if you are trying to make a profit. __________________ Mark Holmes www.daisy3pictures.com Last edited by Mark Holmes; June 2nd, 2009 at 05:17 PM. Reason: typo

June 2nd, 2009, 05:43 PM	#6
Jon Fairhurst Inner Circle Join Date: May 2006 Location: Camas, WA, USA Posts: 5,513	And then there's the web, where 24p takes less bandwidth than 30p. And specifically Vimeo, which throws away frames to achieve 24p. Our older camera did 30p. We encoded 15p for the web, except for webisodes that had single frame gun flashes. If there wasn't much motion, 15p was fine. __________________ Jon Fairhurst

June 2nd, 2009, 09:00 PM	#12
Mark Holmes Regular Crew Join Date: Mar 2004 Location: San Diego, California Posts: 119	Ok, one last post and then I'll let it die. Trust me. It matters. The post house will still take the check, yes, of course. But when you distribute a film, you have to turn over a master to whoever is paying YOU. They, in turn, send your master to a post-production house or quality control firm, whose sole job is to go over the master with a fine-tooth comb, looking for flaws in both the video and audio. They are being paid by the distributor, say, Showtime, or ABC. They are covering their ass by finding flaws in the material. A 30P to 24P conversion can result in the kind of flaws that can lead them to rejecting your master. That is very expensive. But I'm sure you are aware of this; it simply bears repeating. And look over the resumes of the guys who host the RED Centre Podcast. They know what they're talking about. Trust them. __________________ Mark Holmes www.daisy3pictures.com

June 2nd, 2009, 01:18 PM	#3
Mark Holmes Regular Crew Join Date: Mar 2004 Location: San Diego, California Posts: 119	Thanks Peer, it is nice being a nut... __________________ Mark Holmes www.daisy3pictures.com

June 2nd, 2009, 07:24 PM	#9
Jay Bloomfield Major Player Join Date: Feb 2008 Location: Voorheesville, NY Posts: 433	I don't want to instigate another tiring 24p "rant" thread, but other than the clean conversion to film, what is real advantage of 24p? Film has a certain color look to it, but that has nothing to do with frame rate. DOF has nothing to do with 24p, as evidenced by the 5D2. The only thing you get from 24p that is "filmic" is motion blur, because you have less frames per second.

June 3rd, 2009, 12:04 AM	#13
Marcus Marchesseault Trustee Join Date: Nov 2005 Location: Honolulu, HI Posts: 1,961	For all the Europeans on this board and any future Aussie or European customers of mine, I hope for 25/24p. I will still be shooting with the 5D regardless but I hope even more firmware upgrades happen. I just won't be infuriated with Canon from now on since I think I'll be very pleased when I shoot with exposure control. Now that I'm happy with them more completely, I hope for their sake they get 25p working so they can sell more cameras.

June 3rd, 2009, 01:44 AM	#14
Robert Martens Major Player Join Date: Jun 2003 Location: Miller Place, NY Posts: 820	Evan, you are not alone; this precise concern has been driving me absolutely insane for months now, what with the increased prevalence of video modes on still cameras of late. I was beginning to think I was the only one who thought about this. The international compatibility issue I can completely understand. 24p can be converted to both NTSC and PAL rates without the headaches of the other potential cross-conversions, so it makes sense there. Combine that with the fact that the Blu-ray video standard only supports 24p and 60i, not to mention the concern for cost on film shoots, and the desire to shoot 24p makes perfect sense. But, despite the many legitimate reasons you can come up with to support the 24p fever, the podcast hosts seem mostly concerned with the misconception Evan addresses in his post: confusing 30p with 60i. They say "thirty frames" when they should be discussing "sixty fields". The example they give, where audiences can tell commercials from movies, is not because the commercials were shot at thirty frames per second, but because they were shot at sixty fields per second. One could technically say that they were shot at thirty frames per second, but in the context of interlaced video "frame" has a different meaning, and it's only a logical unit of information that itself we never get to see. Each of those frames contains two separate images which, though stored together, were captured, and are ultimately played back, one after the other, giving us sixty distinct points in time represented per second, in stark opposition to both 24 frame per second film and 30p video. The video look that we (at least in the NTSC world) are conditioned to see as "home movies" instead of "cinema" does not come from a measly six additional images per second. It comes from the almost thirty-six extra samples of time you get when you shoot interlaced material in our parts of the world. It's two and a half times the motion sampling that stands out, not a paltry quarter-again addition. Those more experienced individuals out there can more than likely spot the difference between 24 and 30 frames per second, if they're paying attention, but a real, honest-to-God thirty frames per second is not the plainly obvious smack in the face that makes even the least trained home viewer say "this doesn't look cinematic", and speaking purely for the look of the footage, doesn't make a significant difference.

June 3rd, 2009, 02:50 AM	#15
Brian Luce Inner Circle Join Date: Jan 2006 Posts: 2,290	This is a great discussion but I'm voting two thumbs down on the podcast, it's filed with mindless chatter about stolen Red cameras and a lot of yourtaxdollaratwork GI Joe combat stories about winning the Silver Star etc. I didn't make it to the end, I couldn't take it. I caught about 90 seconds midway that had some interesting info re 24p but it's a lot of noise other than that. The OP has a lot of good insight, I hope he revisits his thread. The podcast? ctl alt del. Last edited by Brian Luce; June 3rd, 2009 at 03:25 AM.