Skip navigation
Currently Being Moderated

30p vs 24p

Mar 2, 2011 6:15 PM

In considering which frame rate to standardize on for this series, I'm pondering the benefits, if benefits there are, to 24p vs. 30p. What I see most often in documentation is that 24p gives "that coveted film look."

 

Of course, I plan on doing some shooting this weekend to see how much of a difference I can tell from an emperical perspective, but I thought I'd see if there was a general sense around here of the whens and wheres to use 24p over 30p. I'm assuming that Sony included this option because there are reasons to choose it. But then, it may just be that Marketing wanted more bells and whistles. One never knows.

 

Any thoughts on the benefits of 24p?

 
Replies
  • Currently Being Moderated
    Mar 3, 2011 1:15 PM   in reply to Christopher Duncan

    I always shoot at EITHER 24p or 60p, depending on what I'm doing. If it's promotional/documentary type material, I do 24p. If I'm doing sports or event footage, I'll do 60p. Now, if you're shooting for broadcast, you need to do either 24/30p or 60i because 60p can't be broadcast yet (at least, last time I checked, anyway...) If you're shooting for the internet, then anything will work, though for your purposes I'd recommend not going with 60i/p. I've personally never really seen that much difference between 30p and 24p...

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 3, 2011 2:55 PM   in reply to Christopher Duncan

    In my own tests, 30p gave a "somewhat filmish" look, but not quite there.  24p is definitely there.

     

    My own choices for SD would be 24p for film look, and 30i for video look.  Skip 30p altogether.

     

    For HD I'd probably choose 24p for film look, and for the video look either 720p/60 or 1080i/30.

     

    (On a side note, U.S. broadcast stations are either using 1080i/30 or 720p/60.  While there are other HD specs, they are limited to Blu-ray, Satellite and cable delivery systems.)

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 4, 2011 4:45 AM   in reply to Christopher Duncan

    Christopher,

     

    Is your series going to be broadcast or on DVD, or is it web-only? I'm sure you were discussing these somewhere else, but I didn't follow it

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 4, 2011 8:22 AM   in reply to Christopher Duncan

    I, for one (recognizing I'm in the vast minority here), really like to work with 30p. If I'm working on a project destined solely for the web, I'll work in 30p probably 90% of the time; it creates really nice images that don't require deinterlacing for the web, preserving much more visual quality, and I think the cadence of 30p in the web world tends to look better than 24p. The stuttered look that you get from 24p (which is largely unavoidable--it's part of the "magic") really gets accentuated to an almost unpleasant degree, and the blur caused by the slower frame rate can also result in the compression for the web having to work a little harder--this usually necessitates a slightly higher bitrate to deal with the more dramatic differences between sharp parts of an image and blurred parts of an image.

     

    I've also used 30p for DVD and even broadcast work. What can I say--I just like it. Not every project calls for the "film look" (which goes way beyond just shooting in 24p), and sometimes its just inappropriate. I'd really suggest doing some shooting tests at the various framerates (24p, 30p, 60i) and comparing them. There are differences, but in my experience, the web tends to mitigate those difference a bit, particularly when working with video-sourced material versus film-sourced material.

     

    Yesterday, I helped shoot a project in 1080/30p with an HPX170 and a Canon 7D and T2i; in post, I'll interpret the footage as 1080/24p, and get a nice 1.25:1 overcrank effect. Had we not needed that look, we'd have sourced at 1080/24p. That's not really related to your question, but 30p does have some utility outside of being just a shooting rate.

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 4, 2011 9:10 AM   in reply to Christopher Duncan

    Haha! Well, that's part of it--it's about the suspension of reality. When shooting in 60i, we're more closely replicating what our own internal camcorders (that is, eyes, optic nerves, and brain) see and process. That why when you watch, say, the news, you get the impression of something being "live" and as if you're there.

     

    Shooting in 24p tends to create a more dreamlike, disconnected-from-reality feel. Think about when you watch a movie or a TV drama--it has a much more timeless feel to it.

     

    Much more goes into the film look, including depth of field (what's in focus vs. what's not), the depth of color and shadow, and then more aesthetic things like camera movement or the lack of it. Camera manufacturers have been profitting immensely over the last few years by marketing 24p as the magic bullet when it comes to the film look; the bottom line is that they do that because that part is easy and cheap to replicate. The rest of the factors--of which there are many--require more expense and skill to pull off. Some of that stuff you just can't pack into a camera's sensor or DSP or recording format, especially not at a $3000 price tag

     

    My opinion: content is king, and most of the discussions about technical stuff are moot. For example, I think it's total silliness to listen to fanbois talk about their REDs and shooting in 4K, while in the same breath, they talk about how great it looks on an iPhone. Compose an interesting shot and construct a fascinating story--that's goes much farther than a buzillion pixels with nothing to say.

     

    Hope you'll forgive the tangent Ultimately, doing a few tests will reveal the best shooting mode for you. I'd definitely suggest sticking with a progressive mode, regardless of the frame rate, principally since the web is your primary target now.

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 4, 2011 7:03 PM   in reply to Colin Brougham
    Compose an interesting shot and construct a fascinating story--that's goes much farther than a buzillion pixels with nothing to say.

     

    Quite true, but you have to admit, Star Wars shot on VHS just wouldn't be the same.  I for one am a proponent of both artistry and technical superiority.

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 6, 2011 10:17 AM   in reply to Colin Brougham

    Cannot attribute to which film prof, but one shared, "art pre-supposes technique."

     

    Hunt

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 6, 2011 1:01 PM   in reply to Christopher Duncan

    chris,

    ----------------

    Ah, so the stuttered look is what 24p contributes to the "film look?"

    -----------------

    when movies first started being made ( silent ) the frame rate was something like 18fps I think....  when shown on a 24fps "projector" they look like they are speeded up....thats why so many of the old silent "clips" we used to see in the theatre as kids ( filler between the 2 feature films usually shown for our one ticket in those days )...were so fast...like the keystone cops etc...they moved fast and it was sorta funny to see everyone moving so fast....but in the beginning they were projected at 18fps....and moved " normal "....

    However, the frame rate of 18fps flickered a lot ....and wasnt that smooth.  the "mitchell movement" ( the claw and registration pins and motor etc that makes up the basic movie camera....which drags the film down and puts it in position for exposure ...24 times per second now ) got invented and movie cameras became 24fps.

    one of the reasons movies are 24 fps is simply because the invention of the mitchell movement ( the parts that put the film in the gate and so on for exposure ) was fast enough to get rid of a lot of the "flicker" that you saw at 18fps....

    That mitchell movement is going REALLY FAST ( at 24fps ).....if you were to look at it working ( like open the side door of a film camera and load film and run it for a few seconds....you would see how screaming fast that thing is moving )...

    Now, as time went on the movement got even BETTER ( capable of going faster than 24fps ) ....and you could also make it go slower... which is called overcranking and undercranking the camera.

    Because the projectors are 24fps....if you run a film camera at 60fps everything will look like it is going very slow ( slow motion ).  If you run the film camera at 18fps and project it....everything will look like it is going FASTER.....

    In real world shooting you could undercrank the camera on a stunt to make it look like the action is going faster than it would otherwise look ( help the stunt along a little bit...by undercranking )...

    Or you would overcrank to make something look like it is slow motion.

     

    These fps speeds in the camera are adjustable but 99% of the time the film camera will shoot at 24fps.  And the projector in the theatre is projecting at 24 fps....

     

    This has nothing to do with "film looks" and "aesthetics" etc... its simply the speed of the projectors being 24fps....and the mitchell movement in the cameras....

     

    now time has marched on further and new stuff is being introduced to the old world of film and video.... but at least you know why film is 24fps ( cause projectors are 24fps )

     

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 6, 2011 1:15 PM   in reply to able123

    furthermore....

     

    the 180 degree shutter of the movie film camera is basically a circle that spins really fast...and half the circle is cut off...( gone )...so you have a half circle spinning fast....and part of the time the part that is THERE blocks light from entering the camera...and the other half of the time the half circle is OPEN...allowing light to expose the film....

    This shutter is spinning in time with the mitchell movement so that while a frame is being dragged into position for exposure, no light comes in...and then when the film is in position the shutter ALLOWS light in to expose the film.

     

    Because it is half a circle ( 180 degree shutter )...your 24 fps is a 48th of a second exposure....  unlike a still camera you cannot just use any old shutter speed... the film camera with 180 deg shutter at 24 fps is stuck at 1/48th of a second.

     

    Now, because 1/48th second exposure is not all that fast....things that are MOVING in front of the camera will be blurry if they are moving even at a fast walk....and you dont pan with the fast walk....  in other words, you are going to get blur cause of the relatively slow shutter speed.....  That happens to be part of what people refer to as the " film look"....  with faster digital video camera fps ( and faster shutter speeds) you dont get that blur as much...

     

    the depth of field is really primarily a function of your f stop used...and you get more "blur" in front of and behind your subject the more open your lens iris is...  like F 1.8 will be blurry in front of and behind your subject , whereas F 32 will be more sharp in front of and behind your subject...

     

    all that stuff is important in how soft and pretty things look in the overall frame...and might create the "illusion" of dimension ( depth ) cause of the blur ...only because we are now used to seeing things that way  ( conditioned to think something blurry in background is further away ).

     

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 6, 2011 1:20 PM   in reply to able123

    I mention "conditioned" to believe blurry stuff is further away...due to growing up watching movies and looking at photos...cause that is a "learned " thing...

    babies dont know that out of focus things are near or far and how to judge distance etc...which is why they reach out to touch things as they begin to see stuff....and they 'learn" this as time goes on..  ( as Dave will find out very soon with new baby ! )

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 6, 2011 1:31 PM   in reply to able123

    Depending on the film that you are talking about, FPS speeds of 12, 15, 16 and 18 were used. The push to 24 FPS was around sound, whose fidelity increased, when 24 FPS was used. That became the standard where audio was going to be used, either recorded in camera, or added in the lab.

     

    If one were to poke around a good antique shop (or maybe even the Hunt Archive of Dusty Film "Stuff"), they might find either an old Keystone, or Bell & Howell 16mm, and especially an 8mm projector, with settings for at least 16, 18 and in newer ones, even without sound, 24 FPS. I do not recall having seen any with 12, or 15 FPS, but they did exist.Somewhere in the HADFS, I have a Eumig Dual-8 sound projector, that had a feature to switch from 18 to 24 FPS, by flipping a switch that moved a belt from one pulley to another. One could also change the gate, the drive sprockets, and swap between 8mm and S-8mm. The unit also recorded to mag-striped film. In the day, there were quite a few labs that would stripe the stock, on either the original, or could print to mag-striped stock for S-8mm. At one time, I had a striper, but it was a fussy device, and one ended up with a tiny mag-stripe tape wound around their hands, head, and everything nearby. Not sure what happened to that rig, but it probably was tossed out an open window? It took about 200 miles of that tape, to get a clean stripe on 400' of film.

     

    Bonus question: how does one record smooth audio onto striped stock, if the gate is holding the film for the duration of the shutter, and then jerking it down? [This one's easy, if one has ever loaded a film camera, or projector.]

     

    Hunt

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 6, 2011 1:52 PM   in reply to Bill Hunt

    Bill,

    --------------

    At one time, I had a striper, but it was a fussy device, and one ended up with a  tiny mag-stripe tape wound around their hands, head, and everything nearby.

    ----------------

    I can see the bulldog with tape wound around his head and legs and wondering what the heck are you DOING with this stuff ! ???

     

    ROFL

     

    bonus question answer : ( do I get a sausage point ? -- I'm still waiting for yours to explode )

     

    loops in film above and below gate smooth out the motion of the reels ( film reel and takeup reel )

     

    also, if the loop gets too small in projector - the projection will start to stutter on screen ...to fix you can ( while projector is running --takes a little finesse to do this right ...just the right amount of friction between finger and film ) open the pressure plate on gate and expand the loop....

     

    if you do it wrong LOOK OUT !  you end up with film all over the floor and jammed stuff and PANIC TIME !  haha....

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 6, 2011 2:05 PM   in reply to able123

    hehe...Im still laughing..thinking of the failed loop expansion of running projector...

    Your up in the booth and theres all these people down there watching the movie on a big screen...

    and it starts stuttering and so on...and you hear yells and stuff from the audience ...

    " HEY YOU UP THERE....FIX THE MOVIE ...HEY YOU !!!! "

     

    you look out the little window and see the movie is screwed, look at projector and see loop has shrunk up on you...you open pressure plate and attempt to expand the loop.....the film catches your finger ( too much friction ) and doubles up in the gate and jams and continues running ( really fast ) and film is streaming onto the floor now and going all over the place...the you panic and forget to TURN OFF THE PROJECTION BULB....

     

    LOL....  you see, out of the corner of your eye through your little window the still image stuck on screen turn brown in the center and that little brown dot gets BIGGER AND BIGGER ....as you see smoke from the film BURNING IN THE GATE.....

    AAAAAAAAAAAAAAAAAA !!!!!!!!!!

     

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 6, 2011 2:56 PM   in reply to able123

    Wasn't there someone, within the last few days, who wanted a "burning page/map?" Seems that Ann Bens mentioned a "burning film" Effect - she must have been reading your mind.

     

    Hunt

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 6, 2011 3:00 PM   in reply to Bill Hunt

    yeah, the burning "bonanza cowboy tv series" map thing...LOL....

    except that in my case , when that happened, people down there would start yelling even LOUDER and start throwing popcorn at one another ( for who know what reason...could never figure out what started those food fights in the audience )

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 6, 2011 4:43 PM   in reply to able123

    Well, that was obviously before they started serving yogurt for breakfast, before the dailies...

     

    Imagine yogurt and granola in the theater.

     

    Hunt

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 7, 2011 4:08 PM   in reply to Bill Hunt

    this show has a good replica of the popcorn fights that broke out during poor projecting of film in the theatre that I have experienced up there in the booth... its a pretty funny movie..and peter sellers is this old "projectionist" ...LOL...only movie I ever saw that has an old movie theatre as the main "set" and focus of the story etc.  the "bijou" or something...

     

    smallest show on earth.jpg

     

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 7, 2011 5:25 PM   in reply to able123

    I about died laughing, reading your post about the projector bulb burning a hole in the film.  A friend of mine got his start in video by working as a theater projectionist.  He has some funny stories as well.  I remember watching a movie in a theater one time that was slightly out of focus.  You just want to smack the guy up there in the room.

     

    This post is a "recovered" version.  The forum went offline for about 5 minutes.

     

    BTW, this is totally off-topic, but the Adobe home page looks really good, centered like a good web page, then when you click on the other pages, they align left.  I think all of the pages should be centered.

     
    |
    Mark as:
  • Currently Being Moderated
    Mar 8, 2011 3:42 PM   in reply to Christopher Duncan

    chris,

    -----------

    Web pages that shift around on you is doubtless the modern day  equivalent, eh?

    ------------

    why do they do that !! ??????

     
    |
    Mark as:

More Like This

  • Retrieving data ...

Bookmarked By (0)

Answers + Points = Status

  • 10 points awarded for Correct Answers
  • 5 points awarded for Helpful Answers
  • 10,000+ points
  • 1,001-10,000 points
  • 501-1,000 points
  • 5-500 points