Purpose of Effect of 3:2 Pulldown

[Roman Stikel]

The 3:2 pulldown on the Naoflash. Is that used when recording in 60i? What does it exactly do to improve the quality of 60i recording? When importing into Adobe PPCS5 what would be the appropriate preset? Would you still use 60i, eventhough the 3:2 pulldown is checked on the Nano? Thanks Roman

[Dan Keaton]

Dear Roman,

If you have a camera that does 24p, it may send out the new frames with a certain number of duplicated frames to create what appears to be 1080i60.

The duplicated frames are "Pulldown Frames". The process of adding these duplicated frames is called "adding 3:2 Pulldown" as far as I know.

Now, if you want of extract the original frames from the "original frames plus the pulldown frames" (the duplicated frames), the nanoFlash will do this for you.

All you need to do is to enable Video|Remove 3:2 Pulldown.

This instructs the nanoFlash to only record the "new" frames.

Once you do this you have 1080p24, thus you would use the appropriate preset in Adobe CS5 or any other Non-Linear Editor.

[Mark Job]

Originally Posted by Dan Keaton

Dear Roman,

If you have a camera that does 24p, it may send out the new frames with a certain number of duplicated frames to create what appears to be 1080i60.

....Dan, a good example of this is Canon 24 F. I set my Flash XDR to 3:2 pull down and it removes the redundant *extra* frames inserted by the camera's processor to make 59.94 interlaced fields per second.

Originally Posted by Dan Keaton

The duplicated frames are "Pulldown Frames". The process of adding these duplicated frames is called "adding 3:2 Pulldown" as far as I know.

...Correct.I'm hoping we can get the Jam-Sync feature to work with this 3:2 pulldown removal feature. There is a double processing time here, since you are asking the Nano and the XDR to first remove all the redundant frames, then keep the resulting 24 p in step with a time code generated signal. Time Code timing stability becomes an issue.

Originally Posted by Dan Keaton

Now, if you want of extract the original frames from the "original frames plus the pulldown frames" (the duplicated frames), the nanoFlash will do this for you.

K this doesn't make sense. You only want to remove (the duplicated frames).

Originally Posted by Dan Keaton

All you need to do is to enable Video|Remove 3:2 Pulldown.

This instructs the nanoFlash to only record the "new" frames.

Once you do this you have 1080p24, thus you would use the appropriate preset in Adobe CS5 or any other Non-Linear Editor.

...Uhhh, no you don't get 1080p24. The Nano and the XDR *can* record *True 24p* as far as I know (Although I have never tested this feature), but when you set the Nano or XDR to 3:2 pull down removal, you get what the XDR calls 23.98p on its screen at the bottom, or what Avid Media Composer calls 23.976p This is what through me for a loop. If you attempt to capture or import a XDR 23.98p clip into an Avid 24p project, then it won't work. This is really important to point this out. You have to set your Avid Media Composer NLE Project to 1920 x 1080 @ 23.976 or else the NLE kicks back an error and won't import the video clip (s).

Many folks commonly consider 23.976p, or as some devices and softwares will round the 23.976p to 23.98p, as being the same as standard 24p - It's definitely NOT ! Some NLE's will stipulate using a different project fps preset between 23.976p, 23.98p, and 24p. Avid Media Composer is one, even though you *can* mix multiple frame rate clips in one project. Confusing eh ? I know I was. I had to test everything in order to figure out what the heck was going on with these different designations. Point in fact; Manufacturers have begun referring to cameras and recorder who can capture in regular 24p and "True 24p"

[Dan Keaton]

Dear Mark,

I was using the generic 1080p24 term for 1080p23.976.

Many camera's and many people refer to 1080p23.976 as 1080p24, including Canon and Sony.

I use the term 1080p24 (True) when referring to true 1080p24 as opposed to the much more common 1080p23.976.

[Mark Job]

Originally Posted by Dan Keaton

Dear Mark,

I was using the generic 1080p24 term for 1080p23.976.

Many camera's and many people refer to 1080p23.976 as 1080p24, including Canon and Sony.

I use the term 1080p24 (True) when referring to true 1080p24 as opposed to the much more common 1080p23.976.

...You see Dan ? That's confusing ;-) Believe me, the different NLE's sure don't see em the same way either ;-)

[Luben Izov]

Hi Mark,
All you need to remember is that "film" is 24fps! 23.976 (for digital film) it's a drop frame of 24fps , just as/like 29.97fps is a drop frame of 30fps for TV and that is only in the NTSC world.
Cheers

[Dan Keaton]

Dear Mark,

I answered Roman's questions using the terminology that he used.

He refered to 1080i60 as opposed to 1080i59.94. Many people refer to 1080i59.94 as 1080i60 as it is much easier to say and write.

So, I referred to 1080p24 as opposed to the more technically correct 1080p23.976.

Your XL H1 uses 24F terminology, but it is actually 23.976.



The nanoFlash supports the folllowing actual (technically correct) frame rates of 23.976, 24, 25, 29.97, 30, all progressive. And, of course, the nanoFlash supports the interlaced frame rates.

Panasonic refers to 23.976 as 23.98.

In some cases, it is appropriate to use actual (technically correct) 1080p24. As noted above, the nanoFlash supports this "true" format.

[Mark Job]

Originally Posted by Luben Izov

Hi Mark,
All you need to remember is that "film" is 24fps! 23.976 (for digital film) it's a drop frame of 24fps , just as/like 29.97fps is a drop frame of 30fps for TV and that is only in the NTSC world.
Cheers

...Luben, this definition simply doesn't work. Yes film is 24 fps, but digital film, as you referred to it, can be 23.976p, 23.98p, or *True 24p. There is no one size fits all definition, and this is what leads to all the confusion and other difficulties. Now, you also have folks who refer to 23.976p, or 23.98p as 24p when in fact, it is *Not 24p at all. My point is you will run into problems in various situations with equipment in production and post which is *Not compatible with these subtle variations. One of the biggies is Avid Media Composer. If you try to import a 23.976p, or 23.98p, into a 24p project, then it won't work, for example. You *can import these different frame rates other than 24p (Variations) into a single avid project, such as 29.976i, 30p, or 59.94i in 720 and 1080. You have to set a separate 23.976p or 24p project to get the various variations of 24fps digital in. Now is that confusing or what ? I think it is.

[Luben Izov]

Originally Posted by Mark Job

...Luben, this definition simply doesn't work. Yes film is 24 fps, but digital film, as you referred to it, can be 23.976p, 23.98p, or *True 24p. There is no one size fits all definition, and this is what leads to all the confusion and other difficulties. Now, you also have folks who refer to 23.976p, or 23.98p as 24p when in fact, it is *Not 24p at all. My point is you will run into problems in various situations with equipment in production and post which is *Not compatible with these subtle variations. One of the biggies is Avid Media Composer. If you try to import a 23.976p, or 23.98p, into a 24p project, then it won't work, for example. You *can import these different frame rates other than 24p (Variations) into a single avid project, such as 29.976i, 30p, or 59.94i in 720 and 1080. You have to set a separate 23.976p or 24p project to get the various variations of 24fps digital in. Now is that confusing or what ? I think it is.

Hello Mark,
I can see your frustration here, but, actually the things are not that bad at all. Film is and always will be 24FPS. Avid has option for 24fps, 23.976fps, 29.97fps, 30fps and so on different kind of projects. You choose 24fps only when you are editing real film. Anything shot in North America digitally that refer to 24p is 23.976fps. AVID call that 23.98fps, some call it 23.97, but it is only 23.976 and that is true 24p in North American terms because of TV frequency standards. Hope that helps.
Cheers
;-)

[Adam Stanislav]

Originally Posted by Luben Izov

AVID call that 23.98fps, some call it 23.97, but it is only 23.976

To be precise, it is 24000 frames per 1001 seconds.

[Dan Keaton]

Dear Adam,

Thanks.

Another way to show it is 24 / 1.001 = 23.976

[Mark Job]

Originally Posted by Dan Keaton

Dear Adam,

Thanks.

Another way to show it is 24 / 1.001 = 23.976

Hey Dan & Adam: Now that makes sense !

[Dan Keaton]

Dear Mark,

60 / 1.001 = 59.94

30 / 1.001 = 29.97

24 / 1.001 = 23.976

[Adam Stanislav]

Originally Posted by Mark Job

Hey Dan & Adam: Now that makes sense !

If I recall correctly, way back when the old B&W TV aired at 30 fps (60 fields/s) in North America and 25 fps (50 fields/s) in Europe. When color was added, they wanted to be backwards compatible with the existing B&W receivers, so they did two changes.

(1) They continued airing the B&W signal and added the color difference (as is still done in many digital codes, such as the various MPEG standards).

(2) They slowed down the fps by 1.001, so it became 30000/1001 in North America and 25000/1001 in Europe. They did that so they could fit all the additional color information into the existing bandwidth.

We are still stuck with this anomaly because when we switched to all digital TV, they still wanted to stay compatible with all the analog TV sets (with just a converter box added) that people owned or perhaps still do.

I can only hope that we will eventually abandon this anomaly and go to true 24/30/25 fps in the digital world. The way we are doing it is a pain for those of us who write video editing software because sound continues to use Hz, or cycles per second, so keeping everything synchronized when you trim clips and move them around requires you to be aware of the different timing. It is not too difficult with the 24/1.001 video fps as you can think of 48 kHz as 48048 cycles per 1.01 second, so you have exactly 2002 sound samples per 24/1.001 fps video frame. But it does not workout as neatly with the 30/1.001 fps video where you have exactly 8008 sound samples per 5 video frames. And it gets even more complicated with 25/1.001 fps, where you are perfectly synchronized only once every 25 frames. That is another good reason to shoot at 24/1.001 fps as opposed to 30/1.001 or 25/1.001 fps.

[Dan Keaton]

Dear Adam,

As far as I know, 25 is true in the digital world, as 50i is also true.