Standard 60fps?

[Dale Mccready]

Hi there,

The camera head shoots variable frame rates, but what the site is referring to is the tape system. The recorder always runs at 60FPS on the Varicam and uses a memory buffer while shooting to place frames onto the tape consistently at this rate, no matter what shooting rate you choose.

When shooting 25FPS for example, the buffer creates duplicate or dummy frames and places them onto the tape. So 25FPS is 25 real frames and 35 dummies. The user bits code on the tape when recording ‘flags’ these frames with a 1 or a 0 depending upon whether the frame is a real one or a dummy.

The frame rate converter, or non-linear editing system recognises these flags when capturing, and can discard the dummy frames and lay the real frames out in a new time-base, such as 24, 25, or 30 FPS. When capturing material that was shot at your capture frame rate no other conversion is necessary.

When shooting off speed material, when your shooting frame rate differs from your base frame rate or delivery frame rate such as 25FPS, a conversion is necessary where the frame rate converter or FCP software plugin will retime the flagged footage. If for example your frame rate 50 FPS there are 50 real frames shot and 10 dummy frames added to make the 60 recording format. When converting back to 25FPS, the dummy frames will be discarded and the 50 frames left will be stretched out to the playback speed of 25FPS, doubling the duration of the original footage and appearing as slow motion.

Any ‘over-cranked’ or ‘under-cranked’ footage refers to any footage over or under your base frame rate. Under being (in the case of a 25FPS delivery frame rate) anything between 4 and 24FPS, over being anything between 26 and 60 FPS.

An interesting factoid about the Varicam and ‘under-cranked’ footage, is that the dummy frames give the very same appearance as running a telecine slowly, or ‘step-printing’. So it is possible to get two looks out of one piece of footage, one before, and one after retiming/conversion.

Hope that helps

[Robin Probyn]

Thanks yes that helps,but say for example in the one previous thread to this,some one shot at 60p(fps?) and someone else said they had been told to shoot 60p.So surely this was all slow motion? anyone would no this was a mistake unless they knew it was slo/mo shots needed.
How can you shoot at 60p and it not be slow motion?

Sorry guess Iam a linear thinker! but 60p is 60 fps which in either NTSC 30/29.97 or Pal 25/24 what ever…is going to be slo/mo nes par?

Thanks

[Dale Mccready]

If you choose to shoot at 60FPS there are no dummy frames at all so you wouldn’t see any stuttering of the image if it is not retimed. so it can be used from then on as it is, or if you convert it via FCP or the frame rate converter it will stretch out to 2+ seconds duration for every second shot.

Some people prefer to shoot at 60 FPS to give themselves more detail/smoother motion. Also the footage can be retimed at a later date in most retiming applications as there are no dummy frames to be identified and removed which otherwise requires the use of the frame rate converter or FCP’s software converter.

The photographic effect of shooting at 60FPS and not converting it into slow motion is a temporal oversampling. Normal films shoot at 24FPS and play back generally at 48Hz when projected. This is around the minimum frequency to provide the illusion of motion in a series of still images (which film is) and is called persistence of vision. Playing back a 60FPS movie at 60FPS exceeds this benchmark and would give the illusion of very smooth, detailed and sharp images. Sharp especially because there is less perceptible motion blur per frame shot. (things have less time to move between frames leading to less blur).

[Robin Probyn]

So if you shoot 60fps for tv,you can use it as normal ie not slow mo as well as slo mo?
How can it be used at normal speed if the tv system is NTSC 29.97 or pal 25,what is the method of doing this.You have 2 frames for 1 progressively scanned.
Come to that how does 25fps progreesive scanned footage get onto a 50i tv(Pal)I understand the plasma and LCD tv,s are progressive.

Thanks for your time also,you must be ready to bang your head on the nearest wall!!

[Leo Ticheli]

If you want your finished project to look filmic, do NOT shoot at 60 fps!

It CAN NOT be “retimed” to look like it was shot at 24 fps. Period.

Shoot 60 fps only for slow motion or some special purpose such as “live” sports or a “video” look. If you’re shooting features, interviews, the vast majority of commercials, corporate films, weddings, and the like, shoot at 24 fps.

The forums are filled with help-seeking posts from poor souls who received material that was shot at 60 fps. Don’t be one of them.

Good shooting!

Leo
Director/Cinematographer
Southeast USA

[Dale Mccready]

Absolutely true. If you are wanting a filmic look then 60 FPS is not the way to go.

My previous post does not refer to it being retimed to look like 24FPS. IF 60 FPS is retimed it will be slow motion. The only way around that is to drop frames at intervals (like every second one) to create a more normal 24/25/30 frames, but because of the short interval of exposure it will not look like normal shooting and more like shooting 24FPS with a narrowed shutter angle.

To answer redflag, if you have shot at 60FPS and want to use it in a 30FPS timeline, remember that a second is a second no matter how many frames you stick into it. I believe that if you don’t retime/convert the footage FCP will just squeeze the footage into your timeline as is….

….I just did a test of this (60FPS into a 30FPS timeline without frame rate conversion) and yes, it requires some rendering but it just drops every other frame, and looks stuttery because there isn’t enough motion blur between each frame left over. Equivalent to having shot at 30FPS with a 90 degree shutter setting.

It is one of the interesting things that I believe has emerged about human perception over the last few years, especially as it pertains to film. When HD was being developed there was a lot of talk about using cameras wih very high frame rates such as 60FPS because it would give smoother motion, and more realistic portrayal of reality (since we see well more than 24 FPS ourselves). But this idea got thrown out very quickly as people associated high frame rates too much with reality and quickly came to associate those images with news or documentary information.

When watching film and drama, the visual cue of the subtle flicker of 24FPS signals to the viewer that they are watching fiction, and so they can suspend their disbelief and relax into the story being told. People enjoy the artificiality of film and television, and this is where motion, grain, unrealistic colours, and even black & white (or especially B&W) give the viewer a different world to enjoy, unlike their own, everyday one.

I enjoy the fact that in this area the ‘lesser quality’ option wins out here, and that in the future we may have 32bit Log 4:4:4 4K images streaming across our internet connections, but they will probably only be 24FPS.

[Herb Sevush]

While it is true that standard def NTSC is 29.97, Hi Def has all sorts of frame rate standards – 24P, 25P, 30P, 30i, 59.94, 60i – and on and on.

So you can shoot and playback Varicam footage at 60 frames (actually it is more common to shoot and edit at 59.94 which is simply double the NTSC standard). This works great when down converting because every HD progressive frame becomes an interlaced field – NTSC having 2 fields per frame.

Final Cut Pro allows you to edit at 60 (or 59.94) quite easily with a couple of minor bugs. They apparently didn’t want to be bothered creating a Drop Frame time code system where you would have to drop 4 frames instead of the NTSC 2 frames on every minute except the 10th, so you’re timeline has to be in Non-Drop. Also some of the frame counters can handle counting up to 59 frames but others flip out when you enter a time code like 1:12:15:44 and change it to 1:12:16:14. By and large these problems can be worked around and currently I am working on 26 half-hour shows shot with multiple Varicams at 720P60.

The reasons for shooting at 60 frames are twofold:

The obvious one if image quality. In the unending quality comparisons between the SONY 1280i approach and Panasonic’s 720P it is only at 60 fps that you can make the mathematical argument that the Varicam actually contains more information per second than HD Cam. Information can be measured in “pixels per second”. By shooting twice as many frames – or in comparison with 24P – 2.5 times as many frames per second 720P60 makes up in temporal information what it lacks in size of the individual frame.

The other reason for working at 60fps is less well known but can have more important practical results – audio editing. If you are going to do all your audio editing inside FCP editing at 60 Frames gives you twice the accuracy of standard frame rate editing. Your audio edits can get down to 1/60 of a second instead of 1/30 of a second. That difference can be huge when cutting dialogue, especially If you are cutting documentary style audio. Again, if you are going to work on a project that is going to have it’s audio sweetened and mixed in Pro Tools – where they can get down to much finer points that that – this isn’t as big a deal. But for the rest of us it really can make a difference.

The negatives of working at 60 are increased storage, no Drop Frame timelines, need for faster hard drives to keep up with larger data streams and less “real time” effects for the same reason, and the occasional glitches in final cut pro because of the uniqueness of frames ending in 30 and above.

As for the argument that shooting at 60 is “only good for sports” and doesn’t give you a “film look” – that is total B**lshit.

The “film look”, as opposed to the

[Herb Sevush]

Dale –

As I have posted elsewhere in this thread I think this point of view about frame rates is absurd.

There are many bad artifacts in film that nobdy likes – the stuttering look when panning hard verticals such as fence posts, the bizzare look of turning wheels that strobe and stutter, film titles that hold steady and display the film weave inherent to projection. I don’t think audiances liked films beacuse of this – I think they liked films and put up with this because there was no alternative.

You are confusing the symptoms for the disease.

3:2 puuldown isn’t a “film look” – flm doesn’t have a 3:2 pulldown. Film transfered to video has a 3:2 pulldown. What people repsond too is the quality that was put into most motion pictures and that is sorely lacking in most video productions.

That quality takes time and time is money and no one wants to spend it so instead we hear all this giberish about the film look. “Film Look” video treatments to make standard def video look just like film. What made film look like film was better quality and higher resolution – and there is no “treatment” that can make something with less information look like something with more information. You can’t get there from here.

But yes you can add all the negative aspects of film – scratches, grain noise, 3:2 pulldown stuttering – and make your video look even shittier – this of course is a lot easier than creating a quality product to start with.

Finally, if your argument about human perception associating fiction and imaginattion with poor quality were true – you sited “motion, grain, unrealistic colours, and even black & white” – then why stop at 24 fps – why not 18 or 16, and why not 8mm film while we’re at it. And why only with the visual – I guess the imagination should also be associated with crappy sound – I can see a vast array of imaginatively starved people throwing out their CD’s and longing for the days of wax cylindrical recordings.

I don’t know what you’re smoking but everywhere I look people want large screen TV’s with HD and surround sound speakers. You can’t get anyone to watch an old B&W movie – Bogart and Cagney may never have existed as far as modern culture is concerned.

I do agree with this statement you made about the desire to “give the viewer a different world to enjoy, unlike their own, everyday one.” But that’s the province of art, not crappy craftsmanship. As Hitchcock said “movies are life with the boring parts taken out.” That’s what viewers respond to. The beauty, not the artifacts.

Herb Sevush
Zebra Productions

[Dale Mccready]

Hey there,

My experience has been that clients prefer 24FPS for it’s look when dealing with drama, and I agree that higher frame rates provide greater quality, but we are stuck with the systems that have been developed and my point is that people are now responding to this. Their perception is that a flickery image is filmic because that is what they’ve become accustomed to. Yes of course the ‘film’ look is due to many factors. As a a DP I’d be the first to tell you that good lighting, production design, art direction, costume, make up, colour-correction, print and negative film stocks, lens and filter choices, and the concentrated attention of evryone involved creates the production value and finished feel of a film. No one factor can mimic this.

The choice between shooting and editing 60FPS or 24FPS must of course consider all the factors in a project, the target market and delivery system, and the desired affect on your audience.

The showscan system could well have taken off and now what we would associate with quality could well have become 60FPS, But it didn’t. The traditional development of 24FPS (with a second showing of each frame in projection making 48Hz) in the early days of film was an economical/logistical choice, but has led us to where we are now.

Interesting what was previously posted about 60FPS becoming an interlaced 30FPS, thats a great way of capturing more detail for each field. Can you tell us what result this has with motion? what does it look like? Ultra smooth motion I would imagine. Was the Varicam used shooting with it’s shutter at 180degrees and 60FPS? Did the DP have to then light up to make this decreased exposure time per frame or was the ‘open’ or 360 degree shutter setting used?

[Herb Sevush]

Dale –

I agree with you about where we are now, I just hate it when people defend this system as though it were logical.

As for your questions – 720P60 looks fantastic when down-converted to NTSC. It’s hard to explain, and perhaps the letter boxing helps, but it just looks better than anything I’ve seen shot in NTSC, on any camera. Red’s don’t seem to bloom as much and fine details don’t seem to hum. I haven’t tested to see how much it improves on NTSC interlace artifacts but to the eye it just looks great.

I’m the Director and Editor, not the DP, so I don’t know what they did about the shutter. I know we shot tests in the studio at 24, 30 and 60 just before we started the series. The camermen were new to the Varicam’s and they didn’t like the strobing through the viewfinders at 24 and 30, but that was a minor consideration. Bascially I didn’t like the look at 24. The final choice was between 30 and 60 and I went with 60 because of the better audio editing and also becasue this was my first HD project and I wanted to go with the most information I can record. I can always get rid of info later in a controlled way.

If I had it to do all over again I would shoot at 30. The better aduio editing isn’t worth the costs and headaches of working in a format that no else is working in.

If you want to see what 720P60 looks like the series I’m working on is called “Daisy Cooks!” and will be on most PBS stations starting in September in a standard Def release, with the HD relase starting next January.

Herb Sevush
Zebra Productions