Since DCP is 24fps, why not shoot at 24fps?

[Stephen Pruitt]

Hi all. . .

We are approaching our next feature and I'm interested in learning why a lot of people shoot at 23.976 instead of exactly 24fps since DCPs are exactly 24fps and that would require no conversion.

I can set our audio (SD 788T) to exactly 24fps, as well.

Why do I keep hearing about 23.976?

Thanks.

Stephen

 

[Nick Morrison]

Hi all. . .

We are approaching our next feature and I'm interested in learning why a lot of people shoot at 23.976 instead of exactly 24fps since DCPs are exactly 24fps and that would require no conversion.

I can set our audio (SD 788T) to exactly 24fps, as well.

Why do I keep hearing about 23.976?

Thanks.

Stephen

As I've always understood, 23.976 is the drop-frame timebase that most easily allows for conversion to 29.97, for TV broadcast.

By fluidly converting to 24fps for cinema, and 29.97 for TV, it certainly seems to cover all bases...

 

[andrewhake]

Who gives a flying fuck about broadcast TV?

 

[Nick Morrison]

Who gives a flying fuck about broadcast TV?

I can't tell if you're being serious or not?

It may be hard to believe, but broadcast TV still makes a FORTUNE.

It may be diminishing, but it remains dominant.

ESPN alone made almost $10 Billion in 2016.

As the article above makes clear, that's almost DOUBLE what Disney made from all it's Marvel and Star Wars films.

And ESPN is just ONE network.

Keep that in perspective.

 

[Neil Abeynayake]

Who gives a flying fuck about broadcast TV?

No shit!

 

[Nick Morrison]

No shit!

I'm going to point you to my post above.

Broadcast TV isn't going anywhere.

Digital is coming on strong, but there is a still a massive domestic and global market for broadcast TV, and will be for quite a while.

It makes BILLIONS, and is often widely more profitable than film.

 

[Neil Abeynayake]

I'm going to point you to my post above.

Broadcast TV isn't going anywhere.

Digital is coming on strong, but there is a still a massive domestic and global market for broadcast TV, and will be for quite a while.

It makes BILLIONS, and is often widely more profitable than film.

Calm down. You didn't see the humor of our posts didn't you? Once in a while in life we got to have a bit of fun. You take "shit" wayyyyy too seriously.

 

[Nick Morrison]

Calm down. You didn't see the humor of our posts didn't you? Once in a while in life we got to have a bit of fun. You take "shit" wayyyyy too seriously.

I work in broadcast TV.

Ahh, so that's humor?

Got it.

 

[M Most]

As I've always understood, 23.976 is the drop-frame timebase that most easily allows for conversion to 29.97, for TV broadcast.

By fluidly converting to 24fps for cinema, and 29.97 for TV, it certainly seems to cover all bases...

You have always understood something that is incorrect. Drop frame has nothing to do with the frame rate. It is a numbering scheme that was devised to make time code accurate to real time, and was developed for 60 field systems. The fractional frame rate came into being when color was introduced, and it was necessary to multiplex color images and sound on one carrier. The combination of frequencies prevented this from being done at 60 fields per second, so because of various mathematical necessities, the rate was slowed down to approximately 59.94Hz. The 23.976 came about years later when 24 frame video recording was introduced in HD cameras. This was done by using the same fractional slowdown as 60 to 59.94, making it simple to fit the "24" frame material into a 60 field broadcast world. Today, it is a legacy that is maintained by the needs of broadcast, but also by the rather entrenched infrastructure that was created around it, for both picture and perhaps more significantly today, sound in North America and some other territories.

Now that the history lesson is out of the way, 24 fps recording is widely used in feature work today. There are a few studios that are now mandating it (Fox and Universal), and essentially all post production companies can handle it as long as all production personnel, the producing studio, post sound, and editorial are all on board. We and most other companies involved in feature post production deal with it every day. It's not really a problem at all. You will not, however, encounter it in broadcast production for all of the reasons I just outlined.

 

[D Fuller]

You have always understood something that is incorrect. Drop frame has nothing to do with the frame rate. It is a numbering scheme that was devised to make time code accurate to real time, and was developed for 60 field systems. The fractional frame rate came into being when color was introduced, and it was necessary to multiplex color images and sound on one carrier. The combination of frequencies prevented this from being done at 60 fields per second, so because of various mathematical necessities, the rate was slowed down to approximately 59.94Hz. The 23.976 came about years later when 24 frame video recording was introduced in HD cameras. This was done by using the same fractional slowdown as 60 to 59.94, making it simple to fit the "24" frame material into a 60 field broadcast world. Today, it is a legacy that is maintained by the needs of broadcast, but also by the rather entrenched infrastructure that was created around it, for both picture and perhaps more significantly today, sound in North America and some other territories.

Now that the history lesson is out of the way, 24 fps recording is widely used in feature work today. There are a few studios that are now mandating it (Fox and Universal), and essentially all post production companies can handle it as long as all production personnel, the producing studio, post sound, and editorial are all on board. We and most other companies involved in feature post production deal with it every day. It's not really a problem at all. You will not, however, encounter it in broadcast production for all of the reasons I just outlined.

I so admire how deep your knowledge goes.

 

[Nick Morrison]

You have always understood something that is incorrect. Drop frame has nothing to do with the frame rate. It is a numbering scheme that was devised to make time code accurate to real time, and was developed for 60 field systems. The fractional frame rate came into being when color was introduced, and it was necessary to multiplex color images and sound on one carrier. The combination of frequencies prevented this from being done at 60 fields per second, so because of various mathematical necessities, the rate was slowed down to approximately 59.94Hz. The 23.976 came about years later when 24 frame video recording was introduced in HD cameras. This was done by using the same fractional slowdown as 60 to 59.94, making it simple to fit the "24" frame material into a 60 field broadcast world. Today, it is a legacy that is maintained by the needs of broadcast, but also by the rather entrenched infrastructure that was created around it, for both picture and perhaps more significantly today, sound in North America and some other territories.

Now that the history lesson is out of the way, 24 fps recording is widely used in feature work today. There are a few studios that are now mandating it (Fox and Universal), and essentially all post production companies can handle it as long as all production personnel, the producing studio, post sound, and editorial are all on board. We and most other companies involved in feature post production deal with it every day. It's not really a problem at all. You will not, however, encounter it in broadcast production for all of the reasons I just outlined.

Always happy to learn more.

Thanks as always Mr.Most!

 

[Marc Wielage]

We are approaching our next feature and I'm interested in learning why a lot of people shoot at 23.976 instead of exactly 24fps since DCPs are exactly 24fps and that would require no conversion. I can set our audio (SD 788T) to exactly 24fps, as well. Why do I keep hearing about 23.976?

Some good advice above.

I would add that one key question is: what is the key audience for your production? If you believe the largest gross income will come from theatrical, you can make a good case to go for 24.00fps.

But if it's an indie film where the largest part of its net income will be coming from downloads, streaming, home video, Pay TV, OTT, and broadcast sales, then I'd stick with 23.98fps.

Doing the .1% pull-up at the end of the process is very simple for anybody finishing the show for a DCP, and it's a very well-known workflow that has functioned very well for at least 15-16 years that I know of.

Don't forget that there's a domino effect with camera framerate, because it eventually affects dailies, the sound department, editorial, VFX, and color-correction. Everybody has to be on-board to understand what the project's official framerate will be for production and post. I think either can work provided you have a meeting with everybody and they'll agree and understand with the reasons to choose a specific path.

 

[Blair S. Paulsen]

Working the US I have never had issues with 23.976 working as expected in all departments unless there was operator error. I have had 24fps material that bedeviled sound syncing with legacy analog equipment and some DAWs. These days it's trivial for most newer gear to up/down/cross convert/re-frame/make coffee/etc. That said, over the years, I've seen some very old machines still in service. My philosophy is - you don't know, what you don't know - if you know what I mean ;-)

Since we're on RedUser, props to RED Engineering for offering a plethora of frame rates, sizes and rasters to suit various creative goals and/or match particular lenses. Your efforts are most appreciated.

Cheers - #19

 

[David Battistella]

I pretty much shoot aeverything at 24 because going to 25 or 23.98 is fairly simple. FYI 24, 25 and 30 fps is also a DCP "standard" in 4K

wiki

David

 

[David Peterson]

You have always understood something that is incorrect. Drop frame has nothing to do with the frame rate. It is a numbering scheme that was devised to make time code accurate to real time, and was developed for 60 field systems. The fractional frame rate came into being when color was introduced, and it was necessary to multiplex color images and sound on one carrier. The combination of frequencies prevented this from being done at 60 fields per second, so because of various mathematical necessities, the rate was slowed down to approximately 59.94Hz. The 23.976 came about years later when 24 frame video recording was introduced in HD cameras. This was done by using the same fractional slowdown as 60 to 59.94, making it simple to fit the "24" frame material into a 60 field broadcast world. Today, it is a legacy that is maintained by the needs of broadcast, but also by the rather entrenched infrastructure that was created around it, for both picture and perhaps more significantly today, sound in North America and some other territories.

Now that the history lesson is out of the way, 24 fps recording is widely used in feature work today. There are a few studios that are now mandating it (Fox and Universal), and essentially all post production companies can handle it as long as all production personnel, the producing studio, post sound, and editorial are all on board. We and most other companies involved in feature post production deal with it every day. It's not really a problem at all. You will not, however, encounter it in broadcast production for all of the reasons I just outlined.

So if we are making film then we should always be 24p?
Unless perhaps it might be broadcast on TV, then it becomes trickier and we need to decide between 24p and 23.976?!

 

[Audy Erel]

TV in my region is 25 FPS... (PAL)

 

[David Battistella]

Also, when we are talking about RED we are talking about Progressive frames, that means 1 Frame is 1 Frame, not two fields interlaced and combined to make a frame.

So, the time base of 23.98 or 24 frames will still capture 24 frames. The timebase of 25 frames will capture 25 frames.

Sound sync/recording is based on Timebase and not FPS.

You will have problems if the sound has a different timebase than the camera TimeBase.

IE: If you capture 24FPS and the sound department is "clocking" at 23.98 there will be drift. Both departments need to know the TimeBase and they should be the same.

David

 

[M Most]

So if we are making film then we should always be 24p?
Unless perhaps it might be broadcast on TV, then it becomes trickier and we need to decide between 24p and 23.976?!

You should do whatever your client (studio, production company, broadcast entity, distributor, etc.) tells you to do.

 

[Terry VerHaar]

I can't tell if you're being serious or not?

It may be hard to believe, but broadcast TV still makes a FORTUNE.

It may be diminishing, but it remains dominant.

ESPN alone made almost $10 Billion in 2016.

As the article above makes clear, that's almost DOUBLE what Disney made from all it's Marvel and Star Wars films.

And ESPN is just ONE network.

Keep that in perspective.

Not sure if it matters to this discussion but I don't think ESPN - or any cable network - is considered "broadcast TV."

 

[Marcus Friedlander]

Also, when we are talking about RED we are talking about Progressive frames, that means 1 Frame is 1 Frame, not two fields interlaced and combined to make a frame.

So, the time base of 23.98 or 24 frames will still capture 24 frames. The timebase of 25 frames will capture 25 frames.

David

Slightly off topic I'm sorry, but can someone help me understand how in progressive capture, where 1 frame is 1 frame, you could have a 23.98FPS?

If 1 frame is 1 frame how do you get .98ths of a frame?

I'm sure there's something simple I'm missing, but any help would be appreciated!

Thanks!

EDIT: P.S. And how is that effected by a rolling shutter vs global shutter?