Reason film stayed at 24fps?

I read that they ran it at 24fps because that's the lowest they could go w/o getting really jumpy images, and that they did it as low as possible to save money. I'm pretty sure I read that in the book "Understanding movies" by Louis Gianetti. Some people mentioned here that money wasn't an issue. Is louis full of it?
 
Policar said:
Both Cinerama and Todd-AO were very successful before they were phased out and they were non-standard frame rates projected with non-standard projectors, so it's not as simple as all that. Certainly 35mm will be 24fps for "decades to come" but with digital projection (and the possible reintroduction of sporting events, etc. being televised live at movie theaters in consideration), I wouldn't bank on the frame rate remaining for all theatrical exhibition for too long. It'll be interesting to see which 3D system is chosen (assuming one is, but it's looking more and more likely) since it seems some of them run at different frame rates (and certainly all of them will reshape cinematography massively, since current cinematography is all about adding depth to a 2D plane.)
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cinerama and todd-ao were giant aspect ratios compared to the standard 1.85:1. todd-ao was used on cleopatra, and a few others, like oklahoma, but after many screens weren't able to display the whole frame, they scrapped it. musicals loved using the bigger aspect ratios, because they're production numbers would be captured fully, and at a better resolution. also, todd-ao was disgustingly expensive. money was a huge issue back in the day as it is today too. cleopatra was the most expensive movie for it's time, and they had to shut down production a few times because of Elizabeth Taylor being 'sick'. todd-ao involved all new lenses and a new printing process that was adding up cash register sounds to movie execs.

24fps is the natural standard for motion meeting the speed of the eye. a lot of people have correct information in this thread, but some of it seems to be garbage. have any of you taken film history??
 
Actually the eye can pickup more than 24fps frames per second. Before maxiVision (48fps) there was ShowScan (originally 72fps, then 60fps) They ran tests on a people and found that people could see big differences in frame rates but that distinction would start leveling off at 48fps and certainly minimal by 60fps.
It was always amazingto watch the footage. Water splashing whoudl show all the drops. You coudl watch the wings of a duck. Thsi wasn't slow motion but did acheive a sense of being there. A few simulator rides were done in this format. The downside is it looked a bit like live video since the frame rate is one of the main aspects of 'film' versus 'video'
 
Optical sound ran at 24 fps. At any other speed the sound wasn't reproduced properly over the theatre's sound system. Then it just stuck until it proliferated everywhere. Now its the norm.
 
Barry_Green said:
Now, someday someone will come up with a workable plan for installing digital projectors, and that may change things.
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I believe that Thompson just landed a deal the other day to overhaul some massive number of screens for digital projection. Here, I just found a story:

http://news.com.com/Thomson+lands+1.5+billion+digital-movie+role/2100-1025_3-5943863.html


Edit: of course now I see that most of this information was contained in an article you already posted. Meh.
 
With 24 fps the basic shutter speed is 1/48 with 180 degree shutter. Using faster frame rates like 48 fps would make low light shooting difficult, rob one f-stop.

For HD-video movies of the future 48 or 72 fps would be a possibility, possible to show on digital projectors and easy to convert to normal 24 fps film print.

There has been no reason for theatre projectors to run at anything than 24 fps, and maybe 16 & 18 for old films. It is extremely difficult to make a mechanical projector that could run 35mm film at faster speeds than 24 fps (film tearing, film plane flatness, image stability etc) and digital projectors coming on strong, nobody is going to invest any money trying... And, by the way, aren't modern projectors actually showing each frame twice (simulated 48 fps)???

24 fps is a compromise, and it has worked well for a looong time. And it is going to stay with us even longer.
 
Petrus said:
And, by the way, aren't modern projectors actually showing each frame twice (simulated 48 fps)???
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They flash each frame on the screen twice (or even three times), but it has nothing to do with simulating 48fps. The film runs through the projector at 24fps, and 24 individual discrete frames are displayed on the screen. They use a two-bladed shutter to try to even out the flicker, not to try to simulate a faster frame rate.
 
Of course not, Barry. Showing each frame twice is not 48 fps and that's why is used the word "simulated"...
 
You would be surprised how many people ask this question though. I've had people say "you can never see film at 24fps, the projectors all run at 72fps, etc." They don't seem to grasp the concept that the film moves through the projector at 24 frames per second, and no matter how many times it gets "flashed" on the screen, they're still seeing only 24 unique distinct frames per second. So while I'm sure you know the difference, there are many out there who don't, and so when they read this thread I don't want them coming away with the idea that somehow they're seeing 48fps or 72fps in the movie theater... :)
 
Justin_Kirch said:
cinerama and todd-ao were giant aspect ratios compared to the standard 1.85:1. todd-ao was used on cleopatra, and a few others, like oklahoma, but after many screens weren't able to display the whole frame, they scrapped it. musicals loved using the bigger aspect ratios, because they're production numbers would be captured fully, and at a better resolution. also, todd-ao was disgustingly expensive. money was a huge issue back in the day as it is today too. cleopatra was the most expensive movie for it's time, and they had to shut down production a few times because of Elizabeth Taylor being 'sick'. todd-ao involved all new lenses and a new printing process that was adding up cash register sounds to movie execs.

24fps is the natural standard for motion meeting the speed of the eye. a lot of people have correct information in this thread, but some of it seems to be garbage. have any of you taken film history??
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I've taken lots of film history. How is what I wrote garbage? I'm not saying that it wasn't expensive (it was--cinerama used four and half times the film 35mm did) but most of the cinerama and Todd-AO movies were also hugely profitable. The technologies were phased out as the novelty wore off and the costs were indeed absurd, though. I'm just saying that 24fps may still be the "standard" but there have been other frame rates in recent years that have been successful, so it's not unreasonable to think digital projection may result in some non-24fps content some time in the future. I think IMAX may be another frame rate, too, but I'm not sure.
 
Policar, I wasn't saying your post was garbage. I just happened to talk about Todd-AO because I know a little bit about it. I'm not saying your info was at all wrong, I'm saying overall, the people who posted didn't seem to know why some things are the way they are. No offense at all to you.

- Justin

P.S. IMAX is just sick overall. What size film do they shoot on again? I know it's massive.
 
It's 70mm film printed like vistavision in a 4:3 aspect ratio from the looks of it. So 10 times the size of 35mm, 3 times the size of 70mm.

I've only seen 70mm projected once and it looked outstanding, IMAX is amazing, too, but (like Todd-AO and Cinerama) it's not practical for narrative purposes. (Which is why it's still travelogues, documentaries, etc. which are shot in it.) To be honest, the sharpest anamorphic print I've ever seen definitely compared with 70mm, though (then again, it was Laurence of Arabia verus a brand new print of The Island so technology had time to catch up.) Lenses are definitely improving...
 
So.. to summarize (so far) the reasons why 24fps became the standard:
1. The least amount of film being able (based on persistence of vision) to recreate a continuous motion (economy while delivering a good image)
2. Mechanics being able to pass the stock through the gate without excessive build up of emulsion (there were no registration pins)
3. Slow(er) stocks (back then) requiring less light than if they were shoot at higher frame rates.
4. 24 as opposed to 23 or 25 for obvious reasons.
5. Slower lenses (back then) would have required a lot more light for higher frame rates.
6. "What else?"

Barry, I think you said something about the same frame being flashed twice or three times during projection.
Could you elaborate a bit? (I read the post several times and I still don't get it as "why and which projectors would do that".
 
Most modern projectors use a two-bladed or three-bladed shutter, which results in the image being displayed and then hidden two or three times per frame.

The normal course of projection involves the shutter shutting off the light while the film gets advanced to the next frame, and then the shutter opens to project the frame on the screen. So it's hide-advance-open, hide-advance-open, etc.

With the two-bladed shutter, it flashes the image twice; it goes hide-advance-open-hide-open-hide-advance, etc. The net result is to reduce the visible flicker; instead of flickering at 24hz, it's now flickering at 48hz, which is less noticeable to the human eye. But still noticeable. So some projectors use a three-bladed shutter, which results in each frame being flashed three times before the film advances. That raises the flicker rate to 72hz, which is usually a lot more undetectable to most viewers.
 
dan said:
So.. to summarize (so far) the reasons why 24fps became the standard:
1. The least amount of film being able (based on persistence of vision) to recreate a continuous motion (economy while delivering a good image)
2. Mechanics being able to pass the stock through the gate without excessive build up of emulsion (there were no registration pins)
3. Slow(er) stocks (back then) requiring less light than if they were shoot at higher frame rates.
4. 24 as opposed to 23 or 25 for obvious reasons.
5. Slower lenses (back then) would have required a lot more light for higher frame rates.
6. "What else?"

Barry, I think you said something about the same frame being flashed twice or three times during projection.
Could you elaborate a bit? (I read the post several times and I still don't get it as "why and which projectors would do that".
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I think there is also a aesthetic reason to it as well. Frame rates "could" be changed if noone was happy with the look of 24 fps, but people like the "juddery" look (for fictional drama anyway). It is what they are used to. I wonder whether we would think 24 fps was crap if we had been weened on a higher, smoother framerate...
 
mmm said:
I think there is also a aesthetic reason to it as well. It is what they are used to. I wonder whether we would think 24 fps was crap if we had been weened on a higher, smoother framerate...
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I have big doubts the "aesthetics" were in question (back then) when the decision was taken for 24fps. Now,... (as we have learned a lot more watching other than 24... including TV with 25, 30, 60i, back to 24P from interlaced and slow mo at any rates) yes!
But back then... I doubt it. People were entertained by “new” and no one was concerned about the lack of registration pins in the equipment, unsteady image and many other “taken care of issues” in the same line (contrast ratios and matching color temp of light sources, lip sink sound.... to name a few)
If we knew back then what we know now, perception of frame rates would have been different (as it is!) less the habit of accepting the 24fps as “standard” (I would guess)

More annoying seems to be the decrease in quality programs as the tools got better.
We have the “means” to say it nicer but we don’t seem to find anything nice to say (obviously overall speaking)
Or just because is “easier” to do, we don’t pay attention to details as we used to...?

End result is what we all know and see every day on TV (subject to taste........)
Quantity increase does not automatically mean results at the same quality expected from “craft”. Mass production. Good or bad? Lowers or heightens our standard of living?

“Film industry” says it all! Not a craft anymore. Tight budgets, 12 days/feature!...My Fair Lady.... Charles Chaplin movies still "move" me (70 years latter). My 2c.
 
The answer is very simple my friends, Hybrid C had the right idea, 24 FPS is the lowest #
of frames that produce an image that appears not to FLICKER.
That is why PAL Television is 50 Hz Interlaced (2 fields per Frame of 25)
Your TV NTSC is 60 Hz which gives you 2x 30 Fields.
 
One thing we haven't mantioned in this yet, is that the shooting/display system using 48fps (MaxiVision I believe) is something we should support. While it would increase the cost of shooting film, it would probably create more loader jobs, and image quality is higher if we shot at 48 and projected at 48. The resolution tests are just killer. I would love to rock the 48fps. Also, another reason that 24 is the standard, is that a lot of older cameras, like mine, that are still in use today, do not shoot at any other fixed frame rates.
 
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