Variable frame rates

Are there any DV cmaeras out there that support variable frame rates. I remember hearing on this board that martial arts films slow down the camera to 22 FPS for fight scenes to make them look a bit faster without looking really cheesey. I would like to do this with DV if possible.

Any suggestions?

 

DV=NTSC=29.97fps.

There are some higher-end cameras out there with other speeds, like 24p, etc, but very few cameras are actually adjustable, because no one's going to use that feature. Bear in mind that 99.99999% of DV camera owners don't make films with them, they just shoot birthday parties and stuff. That's why the companies don't bother spending the money in putting it in there.

 

Hmm, I'm wondering whether a DV camera's frame rate is based on technical settings or a computerized one...because if it's a matter of technical design couldn't one just *tamper* with the original design to allow for variable frame rates?

or would it involve a complete redesign of the camera itself?

I know this is not a common practice and would blow whatever factory warantee on the camera, but it's an option I might take if I were to buy a MiniDV cam and upgrade the technical features myself. Since I'm not familiar with the hardware design of DV cams, I'd like to get some input.

 

The easier way to adjust the framerate (rather than tampering with the camera) is just to open the shot in AE or whatever and alter the framerate there.

In fact it was a software solution they used for the slow-motion effects in Episode II (with Padme/Anakin by the lackside retreat)

If it's good enough for them...

 

DV=NTSC=29.97fps.

That's not entirely correct. DV can also be PAL, which is 25 fps.

(DV=NTSC=29.97fps) | (DV=PAL=25fps)

 

True, but I didn't want to start another NTSC vs PAL war. I'm in the USA, I don't use PAL, so I rarely think to mention it anywhere.

 

Adjusting fram rates in post would still result in a loss of image quality...though it's a better solution than *hacking* the camera.

I just wanted to know if the option was possible if I wanted to stay as close to original film cinematography.

Dammit Jim, I'm an engineer...not a film student!

 

Slowing your footage down in post is good as long as your not slowing it down more than 20%. Right around there you start to get a stuttered effect, because your software is simply reproducing existing frames. If you had a variable frame speed you would be able to capture more frames and thus keep a smooth look.
Which would be better.

 

But I want to speed it up, not slow it down.

 

Same principle.

Actually, even better, in a way. (It's been my experience that digitally speeding something up yields better results than slowing it down.)



Rick McCallum loves you!

 

Actually I believe he wanted to shoot it at 22 fps and then up the speed to 29 so that he would apear to be more dexterous than he actually is.

 

If you want to speed up the look of a fight scene, or make the action look more kinetic. Shoot with a higher shutter speed. It will help eliminate motion blur giving your footage a slightly chaotic feel.

 

Can ou adjust the shutter speed on a DV camera? I know the have a slow-shutter effect on a lot of cameras, but an increased speed?

also I don't reall want a 'chaotic' look. Watch the movie 'Iron Monkey' to see what I want. Only I want one character to look that fast while the people she's fighting look normal. If I could adjust the frame rate on a camera I could make shoot it at a slightly low framerate and choreograph the fight so that the 'normal' combatants are moving a little slower than the should. Then when I play it back it will appear that she is slightly super-human and they are merely competent.

By the way the "y" key on my keyboard just went out. I have to copy it from the text on the web page and hit ctrl-V to use it. So if it seems a "y" is missing somewhere in this post, that is why.

I only this could have happened when comp-usa were open

 

If I could adjust the frame rate on a camera I could make shoot it at a slightly low framerate

Sadly Mini-DV cameras cannot shoot at different framerates (that I know of?) even the camera used to shoot Episode II couldn't. However there is no reason why you can't still do your 'Heroine fighter' moving at normal speed, everyone else moving slower, and then speed up the footage in post so she looks super fast/super cool.

The difficulty will not be in speeding up the footage in post (it's pretty easy and I'm sure it will work absolutely fine in principle) but in getting your actors to do their thing at a specific and constant speed. If they are moving too slow, and you need to speed the entire footage up too much, Super-Heroine may start looking like Super-KeystoneCop

But if they can nail the performances, I'm sure it will look a really cool effect. It sounds promising

 

Hear's an wild but probably bad idea. Assuming that your final project will be deinterlaced, you can take your 29.97 interlaced footage and deinterlace it twice (once using the odd fields, and once using the even fields) so that you have new footage running at 59.94 progressive in it's native speed. Then force the frame rate down to 20fps (using only the first of every 3 frames). Finally you speed that up to 29.97 (or whatever your project's frame rate is). Now you have a fight scene that has a 1/3 speed increase (2/3 frame rate decrease) which might be a little too much to keep the illusion. It depends on the fight footage.

OR you can use that expensive software.

 

Actually, DV is probably Computer NTSC and not true NTSC (which means it runs at a full 30FPS instead of 29.97FPS)