DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   General HD (720 / 1080) Acquisition (https://www.dvinfo.net/forum/general-hd-720-1080-acquisition/)
-   -   24p looks fake (https://www.dvinfo.net/forum/general-hd-720-1080-acquisition/83488-24p-looks-fake.html)

James Adams January 9th, 2007 02:56 PM

24p looks fake
 
Ok, I guess I am the guy who thinks everything looks fake now, but seriously, 35mm adaptors look fake and I think 24p looks fake too.

I don't understand why. Lets say that you have an HVX thats being shot in 24p, isn't that supposed to be 24fps, or 23.97? So why does it look so much different than 24fps on a film camera? To me it has quite a lot more of a choppy look. I shoot with an arri sr2 s16 and never have this feeling. If its the same FPS what would make 24p look like crap? Would I have to convert to film and then back to digital to get the look I want?

Hopefully when RED comes out it wont have this same problem and I can finally get rid of the fake 35mm adaptor DOF look as well.

Christopher Witz January 9th, 2007 03:09 PM

I know what you mean.... I actually think that the 30F on my z1 and fx1's look more film-like than the 24F.

Andrew Kimery January 9th, 2007 03:39 PM

Quote:

Originally Posted by Christopher Witzke
I know what you mean.... I actually think that the 30F on my z1 and fx1's look more film-like than the 24F.

The "cineframe" mode (or whatever it's called) on those cameras is a very botched attempt, IMO, to emulate the 24fps motion signature as the cameras can't actually shoot 24fps.


-A

Graeme Nattress January 9th, 2007 03:41 PM

Judder is a function of edge sharpness. As you go down to 24p, if your edges are nasty video-sharp, you'll get judder.

So, RED, with a big sensor, so shallow DOF (helps to keep judder at bay) and no silly edge enhancement as we have more than enough resolution, should look great with respect to 24p motion.

Graeme

Christopher Witz January 9th, 2007 04:36 PM

well actually... I've never used the in camera cf modes.... I use nattress ( love your plug-ins man ) to deinterlace and it still looks choppier than "real film". but.... choosing the 30 instead of 24 looks better to me.

I'm sure that film camera's shutter angle and the physics of "moving" film have something to do with it.

also.... viewing footage looks different depending on the output device I use.... my 720p projector looks much better at 24 than my 30" apple or other tv's.

David Kennett January 12th, 2007 04:46 PM

I keep telling those film folks 24 frames is too slow, but they just won't listen!

Alan James January 12th, 2007 05:10 PM

The reason it looks fake on most HDV cameras is because it IS fake. 24f is just a film simulation, not really 24p. I actually think that most real 24p cameras look better then their celluloid counterparts, because the film never moves in the gate, you dont get any scrates, its just a much cleaner image. The one thing I dont like is digitals low dynamic range. Digital dosnt look like celluloid, celluloid dosnt look like digital. They are two seperate formats. They can be compared but comparing them is like comparing identical twins, of course of one gunna be slightly different then the other, they aren't the same person.


(I wish people would stop calling 35mm "film" when comparing it to digital, celluloid is the substance, a film is the final poduct, weither its shot digital or with celluloid.)

Dave Perry January 12th, 2007 06:32 PM

Quote:

Originally Posted by Alan James
The reason it looks fake on most HDV cameras is because it IS fake. 24f is just a film simulation, not really 24p.

Actually 24p/f is NOT fake. It's the real thing, 24 frames of digital images per second. 24p/f does not refer to film...er, celluloid, because film is not interlaced. 24p/f only exists because of interlaced video. So, real 24p/f is not fake. It's also not film...oops, celluloid.

Rush Hamden January 12th, 2007 09:52 PM

One thing not taken into consideration is the steady stream of digital information in a digital video camera as opposed to the hills and valleys and concentrations of silver halides in motion picture film, nitrocellulose, cellulite, whatever... With film, you are dealing with a multi-layered 3-dimensional chemical material. The way it reacts to light from one frame to the next, from one layer to the next, differs. It differs in minute quantities, but still. So it will always render the world differently than digital video cameras. Apples and oranges.

James Adams January 12th, 2007 10:58 PM

It still does not make sense to me that it would have that much more of a choopy look than 24fps. With 24p one would almost think that there are less frames than 24fps. When someone is running past the camera on on a static shot with 24fps with film it looks nowhere as choppy as 24p even with the detail and shapness levels down all the way.

Even with all of the differences listed I don't think that it should feel like we are seeing a difference in fps

Ken Hodson January 13th, 2007 02:06 AM

24fps is 24fps. If it is too jumpy you have to turn down the shutter speed. That or track the subject. Same rules as film.

Graeme Nattress January 13th, 2007 07:52 AM

Not quite same rules as film though. Film doesn't have aggressive edge enhancement. Over Sharp edges are one thing that increases the perception of judder, and even if your video camera does a real 24p, you could very well perceive greater judder from this.

Graeme

Gary L Childress January 13th, 2007 05:24 PM

I recently edited a couple of Varicam shoots where I thought the judder was excessive. I am sure the shutter was left at whatever the default value for Varicams is. I think if they had dialed up the shutter a little it would have produced a smoother image and still had the nice 24P look.

Alot of people with HVX200's have gone to setting the shutter at 200 instead of the preset 180. It helps with the judder. You just have to be careful not to go much higher or the image gets smeary. It would be interesting to know if the electronic shutters in these cameras produce a measurably different look than an actual hardware shutter in a film camera. Does a 200 electronic shutter really look more like a 180 film shutter. Not meaning to lay those numbers out as correct, just saying that maybe there is a numeric offset between the two to get a similar look.

Gary L Childress January 13th, 2007 05:26 PM

Graemme,
I like your 24p conversion filters better than Magic Bullet for this very reason.
I had planned to buy the Bullet but really thought the judder was bad. Tried yours and it looked much better!

John Dentino January 22nd, 2007 04:11 PM

Projector Shutter, Telecine
 
It's all in the eye of the beholder: Apparently, according to the author of an excellent paper on this subject at http://amo.net/nt/05-24-01FPS.html, the human eye can perceive ridiculously high frame rates, perhaps way beyond 200fps. With LCD monitors having high refresh rates, 24fps looks bad to people who use high-refresh-rate LCD monitors and play high-frame-rate video games because they no longer have to use their brain's capacity for piecing together action from pictures, otherwise known as persistence of vision. They are expecting something closer to what the human eye can actually see, so, of course 24fps looks juddery.

And here's another thought as to why digital 24p looks choppier than analog film: When film is run through a projector, there is yet another mechanical shutter provide a softening of the stark change from frame to frame. The refresh rate is about as slow as you can get. Even When a movie is telecine'd and there is no shutter, we are accustomed to viewing the movie on a cathode ray tube, which has a lower refresh rate. When we view a DVD on an LCD monitor, however, it generally looks choppier, I think.


All times are GMT -6. The time now is 03:02 PM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2021 The Digital Video Information Network