60i or 30p

[Doug Jensen]

Originally Posted by Les Jarrett

Would love to shoot these moving machines in P, but like others here, have had strobing issues..

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.

[Les Jarrett]

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.

[Anton Strauss]

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

[Doug Jensen]

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.

[Doug Jensen]

Originally Posted by Les Jarrett

I suppose the next question is 24p vs 30p.

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.

[Les Jarrett]

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.

[Doug Jensen]

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.

[Enrique Orozco Robles]

"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

[Doug Jensen]

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.

[Tom Roper]

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

[Tom Roper]

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."

[Doug Jensen]

Originally Posted by Tom Roper

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

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.

[Doug Jensen]

Originally Posted by Tom Roper

And for Blu-ray, while 30p can look great, has to be understood 30p is not directly supported by Blu-ray.

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.

[Tom Roper]

Originally Posted by Doug Jensen

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 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.

[Doug Jensen]

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.