24fps vs. 30fps

[Charles Papert]

That's interesting, Michael! I feel exactly the opposite--that video looks more "real" or similar to our regular vision as far as motion is concerned, and film is successful as a storytelling medium because it looks different, altered from reality.

[Alex Dunn]

I think Michael is on to something. Put your hand out in front of you and wave (fingers spread). There's tons of motion blur with the naked eye, and with video (60i) you don't really get that. Therefore, for the purpose of this comparison, the 24p is more real.

Normally, I would argue that video looks more real, because it's definately more harsh and I just assumed the harshness was reality. But I guess I probably shouldn't inject science with philosophy?

[Don Donatello]

if you are going to wave your hand in front of your eyes and then compare it to 24p & 60i whats is your base line for the comparison ?

IE: what shutter speed are you using for 24p and 60i ?

when i do the "wave" my eyes do see a blur and the movement is SMOOTH ... 60i (1/60 ) does not see as much blur but movement is SMOOTH ... 30p 1/60 little blur but jerky movement ... 24p 1/48 blur but jerky movement (viewed 24fps on computer monitor ) .. 24p with normal pull down little blur and odd movement ....

so which matches what i see with my eye ?? IMO - NONE ...
which comes closes ? well if smoothness is high on ones list then 60i ... if blurness is on high on ones list then 24p ....

bottom line 24p /30p/60i all look a little different so why not put those differences to use ...

[Alex Dunn]

More very good points Don. That's why I love these discussions.

But, if you maintain that it's just a matter of opinion, are we to assume that hollywood has just always shared the same opinion about 24fps? I know they didn't come to the frame rate arbitrarily. However, I'm not trying to say that there's one way to do things, but I think it's safe to assume that 24p AND 30p are BOTH more pleasing to most people than 60i. If I want to sell something, I'm making it 30p if 24p is not available.

[Don Donatello]

hollywood started with 18fps .... when sound came to be 18fps just didn't do it for sound ... they settled on 24fps using 2 bladed shutter that broke up light into 48 pulses per second ( later they went to 3 bladed shutters for 72 pulses) ... don't know if final reason was just to find a speed that worked (vs finding the BEST speed for image and sound ) ... seems to me they just found a speed that was acceptable ? .. IMO the 72 pulses is the reason 24/25 fps works .. try watching 24fps without the multiple bladed shutter and light strobing will get to you...

IMO if they were inventing a film camera today 24fps would not be the speed .. i think it would be in the 30-48 fps area and BEST would not win = economic's would come into play, can the viewer see the difference and who has the best advertising to get their speed accepted.
note that IMAX /showscan didn't use 24fps they went 48fps & 60fps ...
24/25fps projectors are world standard because they are everywhere and retrofitting them to run at different speed is NOT going to happen today because digital projection is about to come into it's own ...
up until summer 2003 cinema digital projectors ( in theaters ) did not offer 2k resolution projection .. they offered 1280 x 1024 per Red, Green and Blue channels. Equivalent to 3.9 million pixels ( projection to 33ft wide ) ... Barco now offers a 2048 x 1080 per Red, Green and Blue channel. Equivalent to 6.6 million pixels. ( projection to 75ft wide) this projector is not in any commercial USA theaters yet .. it is being used at some film festivals that barco is sponsoring.

now are theaters going to be buying 2K or lower cost 1k resolution ? all cinema digital projectors in theaters today are 1k rez ... time will tell if they buy the 2k ... will theaters decided that 1k has worked up to now ? will they decide that most persons can't see difference ? or maybe they'll decide to install 2k in large rooms and 1k in smaller rooms ( remeber specs state 1k rez to 33ft wide which is most theaters) ??
but today we have 35mm in large and small rooms and ALL at 35mm resolution ...

DAAAAAAAA now how did i get on projection ??

getting back to 24p, 30p , 60i ... i think if you asked persons in US they would say Video is more real ( they see it NOW) and that based on they associate NEWS (video) with real .... where film in US is more connected to "art". ( not at the moment)

i'm starting to mix 30p with 60i more and more ... i use 60i as the more REAL happening NOW ... i did just shoot a friends short and we used 60i for flash forward , 15p for flashbacks , 30p for NOW. i like having the choice - progressive or interlace and mixing in FILM

most advertisers want their products to look the BEST .. in past many accociate video as cheap looking ..but video today is very different then video 70's- early 90's so i think that attitude is changing ... Music video have been leading the way for past 15 years on "the HOT look" .. what music videos do today commercials will do next week and hollywood will do 6 months from now.

[Russ Evenhouse]

Don,
I kind of thought the same thing. I didn't think that 24 fps was come to by any investigation. It prolly happened to be the best tech available at the time and looked pretty good. But I still think that maybe those young'uns looking for more "gritty reality" today would actually like the 30 fps better than the 24 fpf. 24 fps is cool, and it does have that shuttered look when close to a movie screen, especially with action shots. I think of 007 movies especially. I think of sean connery running and punching in Goldfinger, but even as a kid I wondered why the herky jerky motion. I learned to love it though. but I still think it may be a "raised with " thing.
Russ

[John Jackman]

I have to disagree with Michael's statement. The research I'm aware of on vision says the opposite. The motion blur in film occurs on even fairly slow-moving objects at a distance. Wave your fingers like that right in front of a video lens, you'll have motion blur. Your eyes are much better than film.

On a related and interesting note, I just heard of some research on cat vision that seems to explain why some cats watch TV and some don't. I've had two or three cats that watch TV, most have not. Cat vision is much better than ours, and their brains process rapid motion better -- more like a sensitive camera with a fast shutter speed, less persistence of vision. Apparently the refresh rate of TV is right near the bottom range of cat vision -- so cats that process vision a little more slowly than normal actually see a picture on TV. The oither cats don't -- they just see the the flying spot, perhaps several raster lines, but not a coherent picture. Those are the cats that are completly disinterested in TV.

Most people perceive video as being "real" (sports, news) and associate film with fiction. Part of this is clearly nothing more than convention and association -- what we are used to.

The 24fps frame rate, despite the kangaroo doo that is shovelled around by some profs in academic film programs, has nothing sacred or intrinisically magical. It is simply what we are used to.

24fps was arrived at in the early days of talkies as the absolute bare minimum speed that would allow an optical soundtrack to work reliably. The decision, like most stuff in the film business then & now, was a BUSINESS decision to get away with the minimum footage of film possible. It was not an artistic decision.

[Dennis Hingsberg]

For what its worth perhaps check out this thread on the similar topic of 24P:

http://www.dvinfo.net/conf/showthrea...threadid=16012

[Brad Horner]

I think of my own vision as a mix of 30fps and 24fps. More direct and objective might look like 30fps. Just waking (dreamy) up or thinking looks more subjective, 24fps. Use dof and other techniques to mix it up.

[Dennis Hingsberg]

I just want to point out an important difference when talking about progressive video frame rates when it comes to the 24 frame rate:

24fps displayed on a progressive display like Plasma, LCD screen or computer monitor is a completely different "effect" (if you would call it that) from watching 24fps footage shown on an interlaced display (like your typical TV).

24fps being displayed on an 60i TV undergoes the telecine process which stretches the film rate to match the TV rate. One of the side effects to this is the judder that is experienced when images travel horizontally across the screen. You would not see this if the SAME footage is displayed on a progressive display.

So my point (if I'm even making sense at this point) is that "truly" watching 24fps at 24fps will look hardly any different if different at all from 30fps which is what the title of this thread is.

Having said that, what are we really trying to compare here when we say 24fps vs 30fps? It all depends on whether or not the display is interlaced or progressive. So I completely agree with what Don has said and might suggest that really this thread should have been called 24fps vs 60i.

[Ted Springer]

Dennis, you make sense and I agree. What I think most people are trying to compare is 60i and 24fps on a standard NTSC monitor. On this hardware even 30fps and 24fps have slightly different looks. But on a progressive monitor, it is much more difficult to tell the difference between 30p and 24p as you said.

[Jacques Mersereau]

It was really interesting when we had a Panasonic Varicam come into the
video studio for a demonstration. We hooked it up to an Epson 820p projector
via HD component signal. WOW!

We had our best Panasonic NTSC camcorder (AJ-D400) set up right next
to it and sent it's output to another Epson.

We shot at all kinds of frame rates. 4,12, 16, 24, 30, 48, and 60.

At 60 full frames, the Varicam's image (IMO and the demo cameraman) looked
like super high quality VIDEO. As some say, that 60fps frame rate somehow
seems like whatever is happening, is happening now.

48fps was about the same.

30fps started to strobe and gave a feeling, much like film, that whatever
was happening, wasn't happening now (or here in front of us)
but had what I would call a 'dream like' quality.

This quality was even more enhanced at 24fps. Yes, I could
tell a difference between 30 and 24fps, and so could every
experienced person who was watching.

24fps strobed more than 30. Did it look "better"? Not really, but it did look a bit more 'dream like'. A couple of folks didn't like 24fps as much as 30.
On fast panning shots, 24fps isn't all that great due to lower temporal
resolution.

If I were shooting with a Varicam and had an NLE that could do my wishes,
I would shoot at 60fps all the time, and then have the NLE go back and
grab and repeat frames to give me whatever frame rate _I want_ for that
particular scene.

One thing is for sure, more frames to work with is a GOOD thing.

[Brad Horner]

Jaques that is how I am picturing this process. I am basicaly the virgin here, but I do have experience coming from the Photoshop and After Effects world. I will be getting a XL1s this saturday. I wanted to study this film effect idea as much as possible so I wouldn't have to be sorry that I didn't get the dvx100.

It seems as if you can get a more filmic look from controlling the suspension of disbelief. If the audience knows that you are putting them on then for most movies, it has failed. Someone said here, 'I just don't want it to look like a video'. Like in photoshop; if you add special effects and it looks like a bunch of filters-failed again. What I'm getting at is, for film effect I will be thinking of the big picture. Lighting, color correction, composition, or whatever it takes to fake the viewer.

My own conclusion seems to be where this thread is heading. I am going to think of the 24fps as just one tool. Actually I would rather have the power to bring down the frame rate later as a choice. Does that make sense, to have that choice?
Or am I losing something?

[Jacques Mersereau]

<<<My own conclusion seems to be where this thread is heading. I am going to think of the 24fps as just one tool. Actually I would rather have the power to bring down the frame rate later as a choice. Does that make sense, to have that choice?>>>>


That is/was exactly my concluding point. If you are able to always shoot at 60fps,
those cool video software engineers should be able to figure out a
way to allow for "after the fact" selection of a slower frame rate.
All you really have to do is select certain frames and repeat them
a certain number of times. A big render, but a very cool option IMO.

What Panasonic has choosen to do is different. The Varicam ALWAYs
shoots/records at 60fps, but in the CAMERA's processor, _IF_ you choose a
different frame rate in the menu, that change of frame rate is made
in the camera (certain frames are repeated) *before* the signal is
recorded or output. So, you can't really go back and change it later.

I believe there is another very expensive box that Panny makes that
can do what I am talking about (select a frame rate from 60 unique frames)
in real time, but it is somewhere around the
price of the camera itself.

[John Jay]

<<That is/was exactly my concluding point. If you are able to always shoot at 60fps,
those cool video software engineers should be able to figure out a way to allow for "after the fact" selection of a slower frame rate.
All you really have to do is select certain frames and repeat them
a certain number of times. A big render, but a very cool option IMO.>>


Jacques,

the software already exists - its called Re-timer and can be used for any frame rate - constant or accelerating