1080p30 vs 1080i60

I want to open this "hot can of worms" one more time as it seems there is a good bit of unnecessary confusion and I want to make sure I'm thinking right.

I've been told that 1080i (at 60 fps) looks like video and 1080p (at 30 fps) looks like Film. My understanding is that regardless of resolution (1080, 720 or 480 for that matter) the film vs video look is achieved more by the frame rate than the resolution. Does that sound right to you?

Naturally there is much more involved like lighting and coloring etc that would affect the film vs video look. But I want to know specifically regarding resolution vs frame rate, which one plays a bigger role?

It is my understanding that the confusion in this area is that so often progressive footage is actually shot at 24 fps. Therefore misleading people to believe progressive = film, when in reality it was the frame rate. Anyone want to weigh in on this?

It's neither. It's the lighting and the lenses that give a movie a film look.

All the best,

Tom

"Hot can of worms" is a horrible phrase. Right up through 75 percent of it, you're thinking lunch. Hot can of what? Soup? Beans? Something delicious? Then the whammy comes, and you're left all hungry and faintly nauseous.

To answer your question: 1080p30 does not look like film. You know what looks like film? Film does. Nothing else.

Furthermore, you shouldn't shoot 1080p30, ever. There are circumstances when you specifically want to shoot 1080i60 (or possibly, 720p60), and on those occasions you should break away from shooting 24p because you're doing it with clear motivation. But there's never a circumstance where you want to shoot 30p. Except when you're overcranking, but to keep things simple I'm going to assume that you're not.

Now, here's one of my trademark long, rambly, pointless posts with way too much detail. You are free to skip the rest of this; there won't be anything important between here and the end.

What most people mean when they say something looks like film is that it looks like material that was shot on film and later transfered to videotape for broadcast on television. So when evaluating the phrase "film look" we have to take into account both the characteristics of film itself, and the characteristics of videotape from telecine.

First, film. We shall list its key properties thusly:

? Film runs at 24 frames per second.
? Film has an exposure interval of half of its frame rate, or 1/48th of a second.
? Film has a dynamic range of approximately (depending on stock and humidity and whether the DP is a good person or not) thirteen stops.
? Film has characteristic grain, which varies from stock to stock but which always looks like film grain.
? Film has an extremely shallow depth of field, which is a function of aperture size and image size.
? Film is always soft. There are never hard edges on film, because of the optical properties of film cameras and lenses.
? Film is typically (not always) less sensitive to light than electronic sensors, which means film sets are usually positively flooded with light, which creates characteristic contours of light and shadow.

Now, telecine:

? Video from telecine runs at 60 fields per second (really 59.94 but I'm going to get tired of writing that out) with a 3:2 pulldown cadence.
? Video from telecine has much less dynamic range than the film itself (call it five stops, give or take), so film transferred to video is always color corrected to maintain the desired contrast.
? Video from telecine is, again due to optical properties, always soft. There are never any hard edges anywhere. Everything looks just ever so slightly out of focus, although it isn't.

These things together all combine to create something that's basically impossible to quantify but that's blindingly obvious to everyone with a working set of eyes: that "film look."

If you switch your video camera over to 30p, how many of these things will you be getting? That's right. Zero. You won't be reproducing, approximating, emulating or simulating any of these things. So your footage won't look at all like film, and you'll be frustrated, and you'll decide you're just not talented at all and put down your camera and go become a bus driver or something. And that would be a tragedy, so let's avoid that.

If you want a "film look," the single most important thing you can do is to shoot 24p with a 180° (or 1/48th) shutter. That'll get you further along the track than any other change. It all has to do with motion blur. A frame of film is exposed in exactly the same way a still photograph is exposed: the shutter opens, light sprays onto the film, the shutter closes. But while a still photograph might typically have an exposure time ? that is, the time during which light hits the film ? of 1/250th of a second or even less, in a film camera the shutter's open for 1/48th of a second. That's a long time, as these things go. While the shutter is open, time doesn't stand still; the objects in front of the camera (actors, cars, a chainsaw blade, blood spatter) move. When an object moves while the shutter is open, a blurry image results.

Go find a snippet of a 35mm film print someplace, and look at it through a jeweler's glass. Look real closely. What's the first thing you notice? It's blurry as hell! That's because of the film camera's long (relatively speaking) shutter time. You don't want that kind of motion blur when you shoot a still, because stills are supposed to be (duh) still. But in motion pictures, that motion blur is essential. It's what creates the illusion of continuous motion from what is in reality little more than a high-speed slide show.

So let's say you tick your video camera over to 30p, and simultaneously tick your shutter speed to 1/60. That should be correct, right? Mathematically, I mean? Because 1/60th of a second is half of 1/30th of a second, which is the reciprocal of the frame rate, so that should give the correct motion quality, right?

Wrong. Because it's the amount of motion blur that matters. When an actor walks across the screen, your eye is used to seeing this much motion blur. (You have to imagine me holding my fingers about an inch apart, because I can't be assed to take a webcam of myself doing it.) If you shoot with a 1/60 shutter, you're leaving the shutter open for a shorter time, which means you're only recording this much motion blur. (Imaginary me is now holding his finger about two thirds of an inch apart.) That's less motion blur, which doesn't look right to the eye. And by "right," I mean "filmyishesque." That's why 1080p30 does not look like film. Because it's not like film, in any respect.

You really can't fake 24p with a 180° shutter. You can get quite close; the PAL 25p format actually looks very much like film in terms of its motion quality, and you need to have quite a good eye to spot the difference. But in NTSC-land, there's no getting around it: If you want the motion quality of film, you want to shoot 24p/180°.

Which of course begs the question: do you want the motion quality of film, and if so, why? The answer to the first question is almost always yes. And the answer to the second question is, "Because you don't want your audience to notice your frame rate."

I've used this example before, and I'm using it again: Remember the first reel of "Saving Private Ryan?" The assault on Normandy? That footage has a very distinctive motion quality. It's been called "stroboscopic," or "staccato," which of course is a musical term, but it's a great word for it. Everything seems somehow sharper, more in focus. When an artillery shell explodes and throws up sand, you can actually see the chunks as they fly through the air. Why is this? It's because Janusz Kaminski, the DP on that film, shot those sequences with a short shutter. Specifically, he used a 45° shutter. That would be equivalent to an exposure time of 1/192nd of a second. And you can really, really see the difference. Dramatically.

In that case, Spielberg and Kaminski wanted the audience to notice the frame rate. Or rather, they wanted the audience to notice the dramatically different motion quality of the footage. But unless you're in a similar situation, where you want to use the motion quality of your footage as part of your storytelling, then you don't want the audience to be distracted by the fact that your film looks "different."

(And if you do want to use motion quality creatively ? go big. Kaminski went from a 180° shutter to a 45° shutter, cutting his available light by two stops in the process. It wasn't a little change; it was a big, bold move. Big, bold moves are artistic choices; small moves are mistakes on the part of the filmmaker. At least that's how the audience is likely to see it.)

So let's sum up here: If you want the "film look," shoot film. If you want the film look without spending a fortune, shoot 24p at 1/48. If you can't shoot 24p at 1/48 for whatever reason (your camera just won't do that, and you just spend your last dollar on lavish gifts for the LAFCPUG forum moderators), then don't go for a film look. Go for another look. Make the camera part of your storytelling, maybe. Shoot 60i on purpose. Find other ways to be creative. Because getting close to the right motion quality is worse than being way off of it. Remember: big, bold moves are artistic choices. But getting it almost right is a mistake.

Some other free, no-cost-to-you tips that the pros don't want you to know about: Keep your aperture wide open all the time. That'll give you as shallow a depth of field as your camera's sensor will allow. Use ND filters to control exposure instead of the aperture ring.

Shoot flat; that is to say, expose your shots to avoid clipping either highlights or blacks. Then you can color grade the resulting footage in post to give it a good, contrasty look. Yeah, your footage will start to fall apart on you if you push it too far in grading. So what? A little noise isn't automatically the end of the world; in film, we call it "grain," and the pros spend a great deal of time synthesizing it to add it to shots that otherwise lack it. Push your footage to the point where it's unacceptable to you ? not to some imagined objective standard ? and then back off a bit until you like it.

If your camera has a gain setting, test with it. Shoot really dark scenes with different gain settings until you find the one that gives you a decent exposure with the least noise. That might be -3 db or it might be +6 db, depending entirely on your camera. Once you find it, set it to that setting and put a piece of grip tape over the knob.

Never shoot handheld. Handheld is all the rage these days, and that's good in general, but consumer video cameras lack the necessary mass to make handheld shooting practical. You can fix this by rigging ballast to your camera ? a car battery or two will do the trick nicely ? but it's often easier just to shoot off sticks, or an improvised dolly. If you do rig ballast and shoot handheld, try to keep the camera's sensor plane as close to your own eyes as possible as you move around. We're accustomed to seeing the world through our own eyes, and when you see a camera move that's meant to be POV but that has the wrong properties because the sensor plane was away from camera operator's center of rotation, it looks weird. In particular, do NOT hold the camera out at arm's length and rotate your body at the hips. That's the opposite of doing it right.

Most of all, though, just don't be scared.

While I appreciate the time you took Jeff to explain the details of Film vs digital Video, that was not the question I was asking. You also didn't explain why you feel you should never shoot at 1080p30.

I ask this question in light of a daily TV show I work on. It is a talk show. We recently upgraded to HD cameras and the decisions was made to shoot in 1080i60. The reason for doing this was because, since it's a talk show they want to ensure it looks like "video" and doesn't start to look more filmy. Yeah yeah I know, nothing looks like film but film. Welcome to the digital world. In this case real film is not an issue and the film look is not what we are trying to achieve anyway.

The point here is that I've been told that they are shooting i not p to make it look more like a live video show. My thinking is that it's not the i vs p that might affect this perception as much as the frame rate. Does that make sense?

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You also didn't explain why you feel you should never shoot at 1080p30.

I did, in some detail, but I'll summarize: 30p looks like ass and is distracting to your audience.

It's important to remember that 1080p30 is not a broadcast format. In point of fact, 1080p30 isn't a format at all; there's quite literally no such thing. What people call "30p" for short is, in fact, 30 PsF. You know how a VTR clocked at 48 Hz can record 24p material as 24 PsF, by storing each frame as a pair of fields? That's how 30p works. But if you run 30p material out to a monitor; it's going to show it as if it were 60i. That is, the odd and even fields from the same frame are going to be drawn at different times on the monitor. That's what gives 30p material viewed on a broadcast monitor that characteristic tear-y, jittery, wrong look.

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My thinking is that it's not the i vs p that might affect this perception as much as the frame rate. Does that make sense?

Errr ? not really, but I'm confident that that's my fault rather than yours. I'm not sure what you mean by "i vs p." Obviously you're referring to interlaced versus progressive, or field-based versus frame-based. But it's not like there's a choice between 1080i60 and 1080p60. You can't separate the matter of frames versus fields from the frame rate.

Or am I, as I suspect, totally misunderstanding you?

>Big, bold moves are artistic choices; small moves are mistakes on the part of the filmmaker.

There was a jazz saying that went "a wrong note played timidly is a wrong note, a wrong note played with authority, is an improvisation".

nveer, your question was about the "film look", and why 30p looks more like film than 60i. Well, to break down Jeff's post even further... Part of what he mentioned was about motion quality, motion blur, and of course, about getting lavish gifts for the LAFCPUG mods (the most important point in his post).

One reason why some guys say shooting at 30p looks more like film than when you shoot at 60i. That's partly because we're used to the motion quality of film, and the movement on 60i looks too "video", as it's sampled at 60 hz vs film which is sampled at 24 hz.

But there's more to getting the film look than progressive vs interlaced, which is what the rest of the post is about.


>You can get quite close; the PAL 25p format actually looks very much like film in terms of its
>motion quality, and you need to have quite a good eye to spot the difference.

Well, film in the PAL world is usually shot at 25 fps so that it's compatible with the video systems in the country/region.



www.strypesinpost.com

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There was a jazz saying that went "a wrong note played timidly is a wrong note, a wrong note played with authority, is an improvisation".

That's way better than I said it. I'm totally stealing that.

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Well, film in the PAL world is usually shot at 25 fps so that it's compatible with the video systems in the country/region.

Yeah, I totally said that wrong. What I meant was that 25p has a motion quality that's really very close to the motion quality of 24p, regardless of whether the 24p or 25p stuff is shot on film or digitally. That's not what I said, stupidly, but that's what I was getting at.

BTW, 1080i60 IS NOT 60fps. It is 60 interlaced fields per second, and there are two fields per frame, so 30fps. Running at 29.98. 1080i...i means interlaced, so you then know that the 60 that follows is fields. 1080p30 is also 30fps, but instead of fields, it is full frames.

24p has the cadence of film. And you can shoot 24p over 60i, meaning you get the film look, but still run at the standard 29.97fps.

Jeff needs a job so that he doesn't write so much.


www.shanerosseditor.com

Listen to THE EDIT BAY Podcast on iTunes
[itunes.apple.com]

I'm sorry, Shane, I didn't realize you were getting billed by the word.

My enthusiasm sometimes, often, spills over into verbosity. I'll cut that out. Meantime, all those who dislike the length of my past posts are free ? no, welcome ? no, invited, even ? not to read 'em. I won't have my feelings hurt or anything.

Thanks, Jeff, for answering nveer's original question in detail.

You know I've been extremely interested in this subject but can't find the right words (technical terms) to start a new thread.

By the way, I ask your permission to quote you from this thread elsewhere when I have to deal with this question (with proper reference of course).

I have a related question > the perception of 29.97 fps with 24 fps 35mm film telecined as 23.98 fps, captured as 23.98 into FCP, outputted as 24p progressive and displayed on TV screens that show it as 29.97 fps. Is the .03 fps slow down noticeable? Because 24 fps is the optimum speed for the perception of real motion by the human eye (now I may be wrong about this, but I remember reading it a long time ago as the basis for the original 24 fps standard of motion pictures.)

The reason I ask this is because 24p shot with DVX cameras and displayed over the Internet looks odd to me. It's supposed to look like 24 fps film projected with a film projector, but to me it doesn't; it looks odd. It's like seeing 18 fps still images displayed without blur yet too distinct -- it's jarring to my eye.

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Shane wrote:
24p has the cadence of film. And you can shoot 24p over 60i, meaning you get the film look, but still run at the standard 29.97fps.

What does "shoot 24p over 60i" mean in technical terms? What does it mean exactly, technically, field by field, frame by frame, whatever.... ? Thanks!

Nveer-

I am going to take a swipe at this from a different angle. Unlike many of the folks here I have spent my career working with material that is acquired with video cameras. News, sports, talk shows, etc.

So, when us video people talk about "the film look" it has been traditionally treating the video, so it looks less like video and more like film. No, stop screaming you Hollywood guys, I KNOW it doesn't look like film, but we do it anyway.

This often means increasing the contrast, adding noise to simulate grain, a glow on the highlights, and to your original point, de-interlacing the material. That give us not 60 images a second (interlaced) but just 30. In addition tossing have the data softens the image.

To your question, frame rate does have a lot to do with a film look. Sports looks like sports because we sample time at 60 images a second. In film you get 24, it looks different.

So when your production folks say they want the talk show to look "video" or "live", that is the reason to shoot 60i. 30p for that would look really odd.

MTV has done their awards show in the past with the live cameras set to 24p. Looks odd as hell. That frame rate is for drama. You want live, stick to 60.

-Vance

Jeff Harrell Wrote:
-------------------------------------------------------
> My enthusiasm sometimes, often, spills over into
> verbosity. I'll cut that out. Meantime, all those
> who dislike the length of my past posts are free
> ? no, welcome ? no, invited, even ? not to read
> 'em. I won't have my feelings hurt or anything.

Well I have to say (because nobody else has) that I don't think you should be apologising Jeff. And I don't think you should cut it out at all. Your posts are nothing less than brilliant. You write with amazing clarity and a huge amount of (often self-deprecating) humour. As someone who lives out in PAL-land I sometimes lose the plot when you're talking about the horrendous problems of NTSC but aside from that I visit this forum two or three times a day just to see what you've got into. I doubt that I'm alone in this. Anyone else agree ?

It pisses me off to hear that you've had so long without work. I can partly sympathise - I had 7 months of that delightful little trip myself last year. When I got into this business, I never for a moment anticipated that my use-by date would come up so quickly. Oh well. Perhaps we could ask Michael Horton to set up a new part of this forum for those of us who're getting a bit longer in the tooth ?

Oh and - grumble, grumble - still can't see your pornographic pluge. Last week I was working on an FCP machine at a post house in town and it showed up fine, but it still isn't here for me at home. It's not a problem apart from increasing my sense of paranoia...

>>Anyone else agree ? <<

Agree. A lot.

And I say that with brevity, to be the balance at the other end.

Well, I am going to disagree with some of the comments here regarding what exactly makes "the film look" and why you might choose to shoot 30p.

If you put two video cameras on the same scene, one shooting 24p and the other 60i, the difference is obvious and visceral for most people. Sure, lighting and production value contribute, but the 24p vs. 60i issue is immediately obvious to most eyes whether they actually have the technical vocabulary to describe the "look".

To say "film look" is all about lighting/lenses/etc. is not correct.
That would only mean that you define "film look" as "higher production value".

But everyone in the industry knows exactly what is meant when the term "film look" means.

Now, I work with mostly 60i video projects. A couple of years ago clients started asking for "the film look", so we went down that path.

The first project we shot Vericam at 24p. The client liked it. However, I noticed quite a bit of temporal motion artifacting, similar to a light strobing on all the motion, not just pans. More than you would normally see on a film xfer.

That might have been caused by the DP/Camera ops leaving the camera's shutter setting to default. I did testing on my HVX to reduce that "judder" by changing the shutter angle and it worked pretty well. You just have to make sure you don't go too far and the motion starts smearing.

However, I was not the DP or operator on these shoots so I had no input. Eventually the director started noticing the motion problems as well and asked the DP what could be done
about it.

And we switched to 30p and have not looked back since. You still get the "film look" but with noticeably reduced motion artifacts.

We shoot all our projects that way right now.

So that is the value of 30p. Film look with less motion issues.

Jude Cotter Wrote:
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> Agree. A lot.

Thanks, Jude. I really thought that there would be dozens of people agreeing, so I was mortified that nobody had replied. I've been wondering if I had breached some forum etiquette.

No, it's just easier to slag someone off than to praise them in our culture, for some odd reason. Jeff does a brilliant job of explaining things and lots of people I'm sure are, and will be, very grateful for it. Taking the time or space to say thanks for that is rare. Much more fun to have a go at him for typing so much.

So please keep typing Jeff, as long as your gnarled arthritic hands can take it. Like you say, you don't wanna read it? No gun to your head.

I am also new to working with 1080p30. All of my experiences in the past has been 60i, 24p and 25.

My knowledge of 1080p30 (Sony HDV in this case) is that it is still 29.97fps but both fields are scanning the same instance in time hence no jitters on a freeze frame.
FCP would show the compressor as 1080p30 but vid rate as 29.97 for my HDV 1080p30 clips. So I was confused when Shane said 1080p30 as 30 full frames because my knowledge is that it is 29.97 frames and not 30 full frames.

I found this explanation on Premiere forum on the Cow and it seemed like a good explanation on 1080p30 (psf) as 29.97:

From Tim Kolb
[forums.creativecow.net]

However, many systems (and CineAlta has traditionally been one of these) will still structure the image data as interlaced for reasons of technical ease in various hardware configurations outside of a computer. In this case, the progressive frame is segmented into two fields, even though each field represents the same instant in time. The progressive footage is reconstructed technically in the same way that any interlaced footage is...PPro, or an HDcam deck or an SDI pipeline doesn't know the difference, or care.
---------------------------

So this seems to confirm that 1080p30 is indeed 29.97. Yes?

CHL

Chi-Ho Lee
Film & Television Editor
Apple Certified Final Cut Pro Instructor

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Sprocketz
So that is the value of 30p. Film look with less motion issues.

Very intriguing! Would it be true to say that 30p on a computer monitor one and a half to two feet from the viewer is the same look as 24 fps 35mm film projected with the viewer sitting one hundred feet from the screen? (Subjectively speaking of course?)

Because honestly 24p doesn't look like film to me. The best description of it was given by Koz a couple of years ago: "it sucks the eyeballs out of your head."

>So I was confused when Shane said 1080p30 as 30 full frames because my knowledge is that it
>is 29.97 frames and not 30 full frames.

Shane probably mean they are "full" frames (progressive), as opposed to "half" frames (interlaced).



www.strypesinpost.com

I love Jeff's long explanations. I can read one and feel like i have learned much more than just my 1 answer. Sometimes, he ends up answering the next question i would have formulated.

BUT.........

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Jeff H.
But there's never a circumstance where you want to shoot 30p. Except when you're overcranking, but to keep things simple I'm going to assume that you're not

.

I have always disagreed with this premise. I hate interlaced footage though at times it is necessary.
I dont always like 24p either because of the increased blur. Sometimes i need the something in the middle. Enter 30p

FOR TALK SHOWS it is really nice. you dont get those hot spots/shinny spots on a sweaty or greasy face that you would with 60i. The set make-up is not as intensely need as 60i.

Espn uses it on those halftime interviews for nba and so does the nba channel. Most of the newer sports interviews/Profiles are shoot that way.
30p is much more color grade friendly than any fps interlaced.

nveer

I would HIGHLY recommend shooting your talk show in 1080/720p30. I have shoot at least 50 interviews in DV 30p and about 10 in 1080p30 and i like it.

30p does not look like film but if you spend some time in a color suite you can get some filmISH like sorta characteristics.

I would not suggest filming a talk show in 24p. Thats not the look you want. It feels sorta part-of-a-movie-ish and like an engaging conversation. I have shot about 12 24p interviews and i didn't like the look for that application.

I think that was why they made it (talk shows and interviews). Its a nice graduation from being stuck with the local news look. Its not too filmy and definitely not the shinny monster that interlaced can be.

""" What you do with what you have, is more important than what you could do, with what you don't have."

> > > Knowledge + Action = Wisdom - J. Corbett 1992 """"

>you dont get those hot spots/shinny spots on a sweaty or greasy face that you would with 60i.
>The set make-up is not as intensely need as 60i.

Well, I've never heard a make up artist go up to the cinematographer and say, "hey, y'all shootin' progressive today? Let m'know the frame rate, so i can do the lipstick up real nice and sweet."



www.strypesinpost.com

Me either. But i have had a make up artist add things to compensate for what they see on the screen in interlaced footage.

They may not know what to call it but they do adjust for whats on the monitor. 24p, 30p, and 60i all have different characteristics when viewed on the screen.

Whether the make-up crew are able to name the codec or frame rate is not important. The fact is they do make adjustments based on what they see. As the person who does know what they are seeing, i see that make-up is done differently for interlaced footage than progressive footage.

""" What you do with what you have, is more important than what you could do, with what you don't have."

> > > Knowledge + Action = Wisdom - J. Corbett 1992 """"