24 fps or 18 fps..does it show?

[paul]

As a rule I always used 24 fps, since it is said it guarantees better image quality.

But when does it really show? Only in shots with fast moving objects? Or in still, hardly moving objects as well?


I'm thinking to record my next film on 18fps, to save some money, and for getting a lower camera noise.

Hope you can help,

Best regards,

Paul

[aj]

It is better when transfer to TV is needed. But then 25fps would be best for PAL TV.

Otherwise 18 fps is enough for most.

[paul]

Ok, I got your point, with the 50 Hz for PAL, but does it really show? I know it is difficult to describe.. but what would you say if you had to give it a try?

Best regards

Paul

[Uppsala BildTeknik]

For still, hardly moving objects it doesen´t show as much. For still images (put the camera on a tripod and film a painting on the wall) it doesen´t show at all.

But mostly, it showes. For panning shots and shots with more movement it shows a lot. Specifically shots with objects that move in a constant speed, as cars, slow moving trains and such, 18fps looks a lot jerkier.

In PAL countries anyway.

[Will2]

In PAL countries anyway.

Physics pretty much holds up in non-PAL countries too.

[Mitch Perkins]

[...] but does it really show? I know it is difficult to describe.. but what would you say if you had to give it a try?

The times we've used the five-blade shutter for 24fps on our chain, everything looked "that much more" sharp - slow/fast pan/still, whatever - just the grain moving by faster gave the appearance of greater resolution.

Deciding whether it's worth the extra cash - I guess you'd have to transfer the same bit of film at both speeds and go from there...and it would depend on the project...

Mitch

[David M. Leugers]

I am one who always shoots 24fps, but if the project is set for 18fps from the start, then I say go for it. Besides the benefits of shooting 24fps, one might never know the use of the footage in the future so I always shoot 24fps as my standard. Just something to maybe consider.

[Actor]

If you could compare two clips, one shot at 18fps and one shot at 24fps, with similar scenes, lighting, composition, etc., and watch them side by side then you could probably see a difference. Lacking such a simultaneous comparison I very much doubt that anyone would notice. Anyone who did notice would probably be someone with considerable cinematography experience. I doubt that the average Joe moviegoer/video watcher would notice.

That said there may be times when rapid sideways movement may appear jerky. I've seen this a few times and I think it was a case of camera malfunction (slowing down) but I can't be sure.

Sleep Always was shot at 18fps. I think it looks okay. If you are going to transfer to video I see nothing wrong with shooting the majority of the film at 18fps and shooting (or re-shooting) a few scenes where you anticipate (or have had) problems at 24fps.

[Uppsala BildTeknik]

The difference in PAL countries is bigger than NTSC.
If you shoot 24fps in europe you can get it transferred at 25fps with no pulldown at all.

The difference in pretty obvious, if there is something moving at a constant speed (like a camera panning, a car, a train, and so on).

If there isn´t that much movement in the image... well then it depends on how much (or little) movement there is, and what is happening in the image. Someone walking looks more jerky than someone picking up a cup of coffee and taking a sip.

[MIKI-814]

The reason may be that PAL colour system is 25fps, ok, but each frame is made of 2 half frames so speaking "in terms of movement playback" it would be more realistic to say it is a kind of 50 fps, although in terms of definition it's 625 lines in 25fps...

[Uppsala BildTeknik]

...each frame is made of 2 half frames so speaking "in terms of movement playback" it would be more realistic to say it is a kind of 50 fps...

No. Since each filmframe is scanned progressively both interlacefields are from the same filmframe. And since no pulldown is applied no extra frames are created.

So you get the "movement playback" of 25 progressive frames displayed 25 times per second. Also, depending on your software for playback, you can totally disable the de-interlacing and get a more crisp image quality on your computerscreen or flatscreen TV.

[supa8]

So how does it work when you shoot at 18fps and decide to telecine the footage, then working in PAL (so 25fps) in Adobe Premiere. Do you have to transfer it at 25fps, or 18 and then increase speed?
Or will that look terrible?

[Uppsala BildTeknik]

You can transfer it at either 18fps or 25fps.

Transfer at 18fps and the pulldown is applied while transferring. Correct playbackspeed is achieved.

Transfer it at 25fps and everything will go too fast. If you apply a pulldown in Premiere, fine, it will playback with the correct speed after that.

Note that there should not be any difference in image quality between these two options.

Look terrible? No, but the playback will be a bit more jerky if compared to a film shot at 24fps and transferred at 25fps. It shows a lot in some scenes and not at all in some scenes, it depends on how much movement you have in the image and what kind of movement. Constant movements look more jerky than short moves.

It is not that easy to see any jerkiness if you shoot one guy who stands still, then quickly lifts his hand up and says "Hello", then putting his hand down again. The movement is already "jerky".

It is almost impossible not to see the jerkiness if you shoot a train leaving the station. The train picks up speed slowly, but you can see the pulldown in this clip since the train is supposed to move at the same speed.

Why don´t you just try? Shoot one cart at 24fps and one at 18fps with clips that have movement and perhaps a few slow camera panning shots? Then decide what to use in your projects.

[super8man]

I would call it a difference in FLUIDITY. The 24fps will flow differently than an 18fps scene. And if the scene is that stationary, use a still camera (just kidding).

I like the economy of 18fps in super 8. In 16mm, 24fps is the rule. I would not shoot lower frame rates in 16 unless there was a specific look or capture I needed.

I quite enjoy the look of sailing scenes I take at 18fps in super 8. For me, its the whole point of shooting movie film in the first place - use it as it was intended for best results. If I need more exact accuracy and rendering of detail, I shoot 16 at 24fps.

Cheers,
Mike

[MIKI-814]

I quite enjoy the look of sailing scenes I take at 18fps in super 8. For me, its the whole point of shooting movie film in the first place - use it as it was intended for best results. If I need more exact accuracy and rendering of detail, I shoot 16 at 24fps.

No doubt that 16mm is another story, but there's an intermediate and logical step before buying all the 16 hardware and that (for those who don't have it) which is trying the Super8 at 24 fps :o

After all it's all a matter of money, isn't it?