differnce beetween 18fps and 24 fps
Moderator: Andreas Wideroe
18 fps produces slight flicker and the appearance of subject movement may be a little bit jerky when the film is projected. 24 fps produces smoother looking movement, giving a more realistic representation of real life. I would recommend using 24fps for filming sports. However, the difference between the two filming speeds in terms of fluidity of movement is not huge. Then again, if your subject is moving quite fast, 24 fps would record it as a little sharper because of the faster shutter speed utilised at that running speed. On the other hand, 18 fps would be a little better for filming in low light conditions because of the slightly slower shutter speed. A 50ft super 8 cartridge will give you 2 and a 1/2 minutes at 24 fps and 3 minutes and 20 seconds at 18 fps.
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matt5791
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18fps produces excellent results, but I always shoot 25.
In reality there is very little difference between 24 and 25, except that 24 is the standard rate for theatrical presentation and origination of films that are going to be theatrically presented.
However there is nothing to stop a film maker shooting 25 even though it will be presented at 24 - the audience will never know and some film makers on a budget have discovered that the film lasts slightly longer when presented so it touches 90 mins instead of a little less!
It all depends what you want to do with your films. If you are just recording your personal memories then there is nothing wrong with 18fps. However if you are planning on transfering to video and editing etc and on doing more professional activities with your camera then it is better to select 24/25.
I always select 25 because most of my stuff is transferred to tape and in Europe we run PAL systems which is 25 fps. If you camera only has 24 though you can still transfer at 24 and view on a European TV - you wont notice the difference. (or you could shoot at 24 and transfer at 25 - the cameras are not that accurate anyway)
The only time it becomes really critical is where you are recording sound, and then you need to crystal control the camera (like a quartz watch) so it runs constantly exactly at 24 or 25 fps. This way the sound will not drift and actors lips stay in sync. If you are recording stuff other than dialogue then you can get away without crystal. (lips are very exact things - very very slight drift is noticable).
If you are new to film I would not worry too much about sound at first.
The other thing to think about is that the faster you run the camera the better picture steadiness will be - it is not uncommon for filmakers on a budget to run the camera at much higher frame rates to smooth out hand held shots.
Matt
In reality there is very little difference between 24 and 25, except that 24 is the standard rate for theatrical presentation and origination of films that are going to be theatrically presented.
However there is nothing to stop a film maker shooting 25 even though it will be presented at 24 - the audience will never know and some film makers on a budget have discovered that the film lasts slightly longer when presented so it touches 90 mins instead of a little less!
It all depends what you want to do with your films. If you are just recording your personal memories then there is nothing wrong with 18fps. However if you are planning on transfering to video and editing etc and on doing more professional activities with your camera then it is better to select 24/25.
I always select 25 because most of my stuff is transferred to tape and in Europe we run PAL systems which is 25 fps. If you camera only has 24 though you can still transfer at 24 and view on a European TV - you wont notice the difference. (or you could shoot at 24 and transfer at 25 - the cameras are not that accurate anyway)
The only time it becomes really critical is where you are recording sound, and then you need to crystal control the camera (like a quartz watch) so it runs constantly exactly at 24 or 25 fps. This way the sound will not drift and actors lips stay in sync. If you are recording stuff other than dialogue then you can get away without crystal. (lips are very exact things - very very slight drift is noticable).
If you are new to film I would not worry too much about sound at first.
The other thing to think about is that the faster you run the camera the better picture steadiness will be - it is not uncommon for filmakers on a budget to run the camera at much higher frame rates to smooth out hand held shots.
Matt
Birmingham UK.
http://www.wells-photography.co.uk
Avatar: Kenneth Moore (left) with producers (centre) discussing forthcoming film to be financed by my grandfather (right) C.1962
http://www.wells-photography.co.uk
Avatar: Kenneth Moore (left) with producers (centre) discussing forthcoming film to be financed by my grandfather (right) C.1962
The presentation technology makes a difference as well. My basic digital camera records at 10 fps and I have been surprised at how minimal the actual flicker is. I suspect it is a combination of retinal retention and screen phosphor/pixel retention.
Slow speeds, such as 10 fps, are useful when putting movies onto the web. Obviously the fewer frames per second, the less memory is needed.
Using anything below 16/18 fps on a projector and the result is poor, so it only works on electronic imagery.
Slow speeds, such as 10 fps, are useful when putting movies onto the web. Obviously the fewer frames per second, the less memory is needed.
Using anything below 16/18 fps on a projector and the result is poor, so it only works on electronic imagery.
New web site and this is cine page http://www.picsntech.co.uk/cine.html
I shoot at 18 fps all the time and I never see any flicker upon projection or in transfer. However I do agree that you occasionally get some noticeable "jerky" movement on fast moving objects since 18 fps will not completely fool our eyes.Patrick wrote:18 fps produces slight flicker and the appearance of subject movement may be a little bit jerky when the film is projected.
Re: differnce beetween 18fps and 24 fps
In addition to the other replies -beginer wrote:whats the difference how bad is it
If you are not shooting something that is going fast, you can shoot at 18fps and transfer to video at 20fps. Results are very fine with no flicker.
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super8man
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Just to throuw in a wrinkle:
At 18fps with a three bladed projector you get a 54fps effective presentation. This is required for the "persistance of vision" effect for the human eye. Anything below about 48 or so and you start separating the individual images mentally.
At 24fps in 16mm, projectors are typically 2 bladed. So, that's only 48fps effectively so the trick still works. Using a 3 bladed shutter yields 72fps, well past being able to see any separation of the motion.
Soooo, 18fps should not yield any flicker. If you are seeing it, perhaps your projector is too slow or you are standing too far away from the screen (just like you can see a computer monitor refreshing from across the office building floor (try it and see)).
Generally, the 18fps is MORE than adequate for film presentation. Detractors who say otherwise tend to be versed/schooled in the old wives tale of "herky jerky" super 8 and will easily suggest that 16 is the only way to go.
Cheers,
m
At 18fps with a three bladed projector you get a 54fps effective presentation. This is required for the "persistance of vision" effect for the human eye. Anything below about 48 or so and you start separating the individual images mentally.
At 24fps in 16mm, projectors are typically 2 bladed. So, that's only 48fps effectively so the trick still works. Using a 3 bladed shutter yields 72fps, well past being able to see any separation of the motion.
Soooo, 18fps should not yield any flicker. If you are seeing it, perhaps your projector is too slow or you are standing too far away from the screen (just like you can see a computer monitor refreshing from across the office building floor (try it and see)).
Generally, the 18fps is MORE than adequate for film presentation. Detractors who say otherwise tend to be versed/schooled in the old wives tale of "herky jerky" super 8 and will easily suggest that 16 is the only way to go.
Cheers,
m
My website - check it out...
http://super8man.filmshooting.com/
http://super8man.filmshooting.com/
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matt5791
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I know that this debate has gone on for years, but it is not just the smoothness of the projected image that is in issue here (although 18 definitely produces more flicker)
There are other issues, which make 24/25 far superior.
Firstly it enables much smoother camera work, especially when you start to run at longer focal lengths. Secondly, because the shutter time is shorter when running at 24/25, you yield a much sharper image. This is obviously especially true where there are moving objects in the frame. It also it means you can run at a wider aperture which reduces depth of field (which I see as a positive with Super8).
These three issues are important to me when shooting film. If you are not so bothered about them then 18 is fine and will yield excellent images
(provided you do everything else right)
In an ideal world we would shoot and present everything at around 60fps :!:
Matt
There are other issues, which make 24/25 far superior.
Firstly it enables much smoother camera work, especially when you start to run at longer focal lengths. Secondly, because the shutter time is shorter when running at 24/25, you yield a much sharper image. This is obviously especially true where there are moving objects in the frame. It also it means you can run at a wider aperture which reduces depth of field (which I see as a positive with Super8).
These three issues are important to me when shooting film. If you are not so bothered about them then 18 is fine and will yield excellent images
(provided you do everything else right)In an ideal world we would shoot and present everything at around 60fps :!:
Matt
Birmingham UK.
http://www.wells-photography.co.uk
Avatar: Kenneth Moore (left) with producers (centre) discussing forthcoming film to be financed by my grandfather (right) C.1962
http://www.wells-photography.co.uk
Avatar: Kenneth Moore (left) with producers (centre) discussing forthcoming film to be financed by my grandfather (right) C.1962
How proportional to exposure difference is 18-24fps? got my films back shot last weekend at a club. a lot of incredable exposures with the stage lights. shot at 24fps for sound sync reasons, i'm debating using 18fps tonight to increase exposure success. the other option is to push process the VNF but don't know concequences. i've had better results with 18fps, but it was also 1.2 cam, possibly more light too.