60i or 30p
 

I am freelancing on a project with my old station, they have the F-350's, their first HD camera. We are trying to figure out if we should go 30p on the project, or go 60i, which is what they are familiar with.

there will be lots of nature and action shots.

I was leaning to 30p, but they don't know much about it, and think 60i would be better.

any thoughts?

How will the programme be shown?

I much prefer P these days, it gives me far fewer issues in post production and is easier to standards convert. But if you have lots of fast action then I may be better.

all the video will air on TV. The video will be of the Iditarod, so lots of dogs running down a trail. so it's not like a race car, or a plane.

Now there's an event I'd love to shoot.

I think interlace would better suit the action and if your production is a straight forward factual documentary this may be the best approach. However if you are making a "film" about the Iditarod then P would give it a bit of the film look.

What I learned
 

The new trick this old dog learned when dealing with 30p is to ignore the viewfinder. 30p looks horrible on the camera viewfinders, and it will scare anyone with you that doesn't know any better. We work with small crews, so we rarely take a monitor with us on shoots. I fought against 30p for a couple of years because it looked so bad on the camera viewfinder. The viewfinders simply cannot handle horizontal motion. I finally figured out that the 30p stuff looks pretty darned good once viewed on a real monitor. We've found that 30p works very well with green screens, and it helps when re-encoding video for web delivery.

I'm still not completely comfortable with 30p because, after all, I am still an old dog, and new tricks are hard to learn. But eventually, facts over come even stubborn minds.

Thats a good approach!

ULi

That's a good point Tim, P does tend to look much more juddery on CRT viewfinders.

I have just the opposite reaction. I've only been shooting 30P during the last four years, and when I see interlaced on a viewfinder my first reaction is "what the hell is wrong with this camera?".

Doug: It's strange how we become used to seeing things in a certain way and when it's different to your "norm" it looks wrong. After shooting and working with P for the past 5 years I like you now find that I looks wrong. I also don't find I notice the "filmic" cadence of feature films as much as I used to.

On a similalr note, when I travel to Europe, it takes me 48-72 hours to get used to the flickering lights all around me. I can't even stand to watch TV in the hotel room.

out of curiosity, is there a shutter speed setting you found that helps improve juddery pans when shooting p

I have a feeling 30p looks smoother, but I am in Pal country and would need to shoot at 25p and it looks bad, so I am still shooting 50i

My default shutter speed for 30P is 1/60th. Sometimes I'll go up to 1/80th for action, but that is my limit. Any higher and I can see the strobing.

Sometimes I'll turn off the shutter (same as 1/30th) in low light but that is rare.

For 25P and 50i, you'll want to make 1/50th your default speed.

okay, let me test again for awhile to see if I can get used to it

30 P Shutter Speed
 

Doug, on my 350 the shutter goes from 1/60th to 1/125th. No 1/80th. Am I missing something?

I shoot transportation subjects, and, like others here, I've primarily shot in I. Would love to shoot these moving machines in P, but like others here, have had strobing issues.

Any thoughts greatly appreciated.

Les,

I use the camera's ECS Shutter mode to get just about any shutter speed I want, so I'm not limited to the camera's normal preset speeds. 80hz is about the same as 1/80th.

On my F350, I am usually happy with 1/60th for just about everything I shoot, but on my F800 I have found myself gravitating towards 1/80th as my normal shutter speed. I can't explain why the two cameras would behave differently, but to my eyes, the F800 requires a little faster shutter speed to minimize motion blur.

Make sure you're judging the strobing by looking at a proper monitor. Don't judge it by what you think you see in the viewfinder. I highly recommend P for everything. There's nothing wrong with shooting action with P. Think about this, every 16mm or 35mm film you've ever seen was basically shot with progressive settings.

Life is a learning curve!
 

Doug,

Thanks so much for your help, I'll experiment with the shutter settings to see what works best for me. I had tried shooting 24p some time back, had motion problems when watching in the monitor. I had tried various shutter settings, but for some reason, had never gone lower than 125th, so never found the "sweet spot".

Most of our customers have given rave reviews to the look in 1080i, but our largest distributor recently demanded everything to come to them in P.

I suppose the next question is 24p vs 30p. Almost every thing we do goes direct to Blu-Ray and DVD. I'm using FCP to edit, then export to a Windows machine to author in Sony DVD Architect.

Thanks again to everyone who has helped the last couple of years. This forum is a real resource.

my camera does not have 1/50 shutter speed when shooting 25p

in ECS I can choose 1/49.8 or 1/50.3 but there is nothing exactly at 1/50

it does not look right using either one, so for now I stick to 50i, it looks lots better

Anton, are you sure your camera doesn't have 1/50th? I find that very hard to believe. All the XDCAM cameras can shoot 1/50th in the PAL mode. What camera are you talking about?

Also, beyond that issue, you could never tell the difference between 1/50, ECS 49.8, and ECS 50.3. To the human eye, they would all look the same.

30P unless you're actually going to transfer to film.

When 24P is displayed on a standard NTSC TV it will add 3:2 pulldown to the signal.

What do you think is better? To shoot those missing 6 frames per second -- or have them interprolated from the other 24 frames? I'd rather shoot 30 fps and have 30 real frames instead of 24 real frames and 6 artificial frames.

Doug,

Shot some traffic on the city street at 1/60th. Looked great until right before the cars left the screen and they were blurry. I'll play with the ECS settings until I get the look I want. Thanks again for your help. BTW, I enjoyed your DVD when I got the 350. I carried it around on my shoots. Sadly it came loose in it's case, and after one trip of bouncing around in the back of the Jeep it got hopelessly scratched. But what a great resource. Keep up the good work.

Les,

Don't forget that some blur is absolutely necessary if you want natural looking motion. If the cars exiting the screen were coming towards you, and therefore going relatively faster as they covered more distance across the frame, that sounds perfectly normal. You wouldn't want the car in a freeze frame to be sharp. If it was, then the moving video would look stuttery and stobe-like. Having said that, I'd rather err on having the shutter speed too slow than too fast.

On most cameras that are set to shoot 30P, 1/60th is the right number. But like I said, right now I feel that 1/80 on the F800 gives me the right amount of motion blur. Ask me again in two months and see if I still feel that way. :-)

Sorry to hear about the scatched disc. I'm sure that if you send an email to sales@vortexmedia they will happily exchange it for just the cost of shipping.

"When 24P is displayed on a standard NTSC TV it will add 3:2 pulldown to the signal.

What do you think is better? To shoot those missing 6 frames per second -- or have them interprolated from the other 24 frames? I'd rather shoot 30 fps and have 30 real frames instead of 24 real frames and 6 artificial frames. "




.... but DVDs (or BluRays) from real 24p - film looks great on NTSC TVs !!!!

am I missing something here ??

regards

I never said the that 24P pulldown might not look good, it's just that I'd rather shoot those extra 6 frames than have them interprolated in my productions. I'm not making Hollywood movies that will need to be transferred to film, so I have that option. If you want to shoot 24P to try and give your productions a "film look" then go ahead, but I don't think it will fool anyone unless all the other production elements mesh together to complete the illusion. That's just my opinion.

Frames are not interpolated in 24p, they are repeated in a 3:2 cadence.

And for Blu-ray, while 30p can look great, has to be understood 30p is not directly supported by Blu-ray. The 30p will be encoded to PsF (progressive segmented frames), and carried within a 60/i interlaced stream. The interlaced progressive fields may be recombined into 60/p progressive output on some players.

From Wikipedia:

"With PsF, a progressive frame is divided into two segments, with the odd lines in one segment and the even lines in the other segment. Technically, the segments are equivalent to interlaced fields, but unlike native interlaced video, there is no motion between the two fields that make up the video frame: both fields represent the same instant in time. This technique allows for a progressive picture to be processed through the same electronic circuitry that is used to store, process and route interlaced video."

You're right, that's the terminology I should have used. But repeating frames, interprolation, pulldown, or whatever someone wants to call it, is still inferior to shooting the full 30 fps to start with.

I would defy anyone to tell the difference between 30P displayed as 60i or 30P displayed natively. To the viewer, they are identical and therefore the technical difference between them is irrelevant.

I think inferior is the wrong word to use as well, since all Blu-ray players and most HDTV's do now include a native 1080/24p display mode, which does not need any repeat frames.

Now if you are just taking a position of 30 fps is "superior" versus 24 fps, that's fine but the argument has been beaten to death by proponents on both sides ad nauseum, including another group that argues 60 fps is superior. Obviously, the higher you go the better the temporal resolution.

Getting back to the original question, I don't see much justification for shooting 24P, and plenty of reasons not to shoot 24P. Of course, if someone disagrees, they are perfectly welcome to proceed down that path. That's why the camera has options. If someone has to ask the question, then 30P is probably the answer they should be given. I would classify 24P as being an advanced workflow that should not be undertaken lightly.

Not arguing asthetics, 24p is a PITA for me. But there's a huge cadre of 24p supporters. Why else the hue and cry to Canon to add 24p to the 5DMkII dslr? I also hear it commonly stated, that if you want worldwide compatibility, 24p can be speeded up to 25p, or 25p slowed down to 24p all very easily. And either one with the appropriate 3:2 or 2:2 pulldown can work on 60/i or 50/i broadcast systems. But to convert 30p to 24p or 25p gives terrible results. So how do you make 30p play nice on the PAL systems?

Because otherwise, I think you are just stating a preference for the asthetic look of 30/p over 24/p which I would agree with, if that's all there was to the issue. But that said, 24p can look stellar on Blu-ray, as the other poster noted.

So my only concern with 30/p is if you use it, you've created a bastard child.

you may hit me over the head

I was checking all available shutter speeds when in interlaced mode and the lowest listed is 1/60 besides ECS

once switched to 25p, 1/50 magically appears

but I believe that in your case, progressive shooting will look better than in my case because you have extra 5 frames each second

also, 30p is not part of the DVD or Blu-ray spec, I wonder what is your delivery format

OK folks, I've had a chance to do some testing. Since there were posters that were arguing for 24p, I decided to test shooting traffic in 24P, it being the more restrictive of the two.

I set up alongside a busy street during the evening rush. Speed limit 40 mph, so some cars were going slower, some faster.

I went through ECS settings and shutter speeds ranging from off to 1/125th.

The best results I obtained was at the lower settings, where cars would start to blur just past the center of the screen (this watching on a monitor).

At higher settings, the blur began to be replaced by judder.

As a control, I shot about a minute at 60i, 1/125th.

It looked nice and smooth, with cars blurring only as they approached the very corner of the screen.

I know that most everything I watch in HD on television is shot at 24p and looks lovely.

But for the life of me, anything I shoot that has much motion, shutter on, off, high, low, does not look good in 24P.

Is there anything more than setting the fool thing to 24P, turning on the shutter and adjusting it to the desired setting?

My distributor wants blu-rays in 24P. Right now, it seems to me it will look better to shoot in 60I, and try to go down the frightful road of standards conversion.

Thoughts? Thanks again. I enjoy hearing the different points of view!