24 or 30
 

In five days I'm heading to Israel with my black Hero 3 to shoot a documentary of my backpacking trip on the 600-mile National Trail.
I'm planning to shoot protunes. But the question is 24p or 30p? Does anyone have any experience with either? The "only" reason I was leaning towards 24p was to keep open the possibility of producing some blu-ray discs. (Why, I'm not sure, because I end up only selling a couple!) I'm aware of the limits imposed on panning speeds too. As well as that "choppy" film rate look.
Should I just dump the blu-ray dream and go 30p for fewer complications and smoother motion?

Re: 24 or 30
 

You can't do a Blu-ray if you shoot in 30p?

Re: 24 or 30
 

I checked wiki for blu-ray specs and they said the format supports 24p but not 30.
Please tell me I'm mistaken!

Re: 24 or 30
 

You should be able to output your timeline at 1080i

Re: 24 or 30
 

You are correct. No 30P for Bluray only 24P or 1920x1080 60i or 1280x720 P60 . Personally I always shoot 60P with my GoPro.

Ron Evans

Re: 24 or 30
 

Unless you are taking a tripod to Israel I would be shooting in 60p. You intend to wear this camera on your person a lot don't you? Also for reliability, I would drop the Protune mode and only shoot with Sandisc Extreme Pro micro cards.and the new FW update.

Re: 24 or 30
 

Yes, I've got the new update.
After hearing your comments and also talking to customer service at GP, I guess I will dump PT. I just don't need the hassle.
Is the 60p recommended because it's much "smoother" than 24, regardless of whether I need slo-mo (I don't) or not?
Yes, half the time I'll be "wearing" the camera and the rest of the time using a tripod.

Re: 24 or 30
 

Actually you can export 30p video on Blu-Ray by creating a 30psf stream. This will be recorded as a 30i file as far as the disc is concerned, but will play as a 30p video.

Re: 24 or 30
 

I was quoting the spec. As far as what one can do to fit in the spec is another thing altogether. For most NTSC sets the refresh rate is 60P so 60i, 60P or any other frame rate will get converted in the set or player to this refresh rate. Unless the TV has a refresh rate a multiple of 24 ( like 72hz, 120hz or 240hz ) then 24p will have pulldown applied to also conform to the refresh rate. The cadence one sees on a TV when playing film that makes it look different to seeing the film in a real cinema. 24P may look even worse on a PC which is why 30P is more preferable for PC playback if one insists on a low frame rate. Personally I can't wait to change all my cameras to 60P.

Ron Evans

Re: 24 or 30
 

Thanks. I'll take that into consideration. (I noticed my TV seemed to be introducing some artifacts into the 24p stuff I was playing back thru the HDMI output.)

Is there any consensus regarding the look of 720 p60 (which is supported by blu-ray) vs. 1080 p 60? One noticeably sharper than the other? Pretty much the same? (I know there's less hassle editing one over the other.)

Re: 24 or 30
 

Unless you're looking for a specific look, you have more flexibility shooting 30p than 24p, IMO. This has always been my understanding; 60i format shoots 60 fields a second which get combined into 30 frames a second. If going to Blu-ray, you output your 30p footage at 60i. Someone please correct me if this is inaccurate.

Re: 24 or 30
 

If you are concerned with only shooting what is native to Blu-ray, 1280x720 60p is the only 60p acceptable format at this point. Just a suggestion, but why don't you shoot what you're typically comfortable shooting, and editing in, and not stress over it.

Re: 24 or 30
 

60i does not combine into 30 frames per sec, that is the timecode for 60i, the fields stay as fields and the TV deinterlaces into 60P for a LCD or Plasma. Of course for CRT's they actually display the fields, 59.97 per sec. These are the horizontal lines one sees if looking up close at a CRT TV. For the purists 60i is actually 59.97 fields per sec and 29.94 frames per sec timecode. LCD and plasma use various techniques to fill in the missing scan lines. A camera shooting 60i has 60 true exposures in the camera, just like 60P but only fields ( half the vertical resolution as odd or even scan lines) are recorded or transmitted. Temporal motion is the same for 60i as 60P. How good a job of deinterlacing the TV does governs how good the picture looks compared to true 60P. On my Sony 240hz TV I can't tell the difference between 60i or 60P from my cameras that shoot both frame rates. The Sony 240HZ TV interpolates the missing scan lines from the interlaced fields effectively reconstructing the full 60P frames and also interpolates more frames to smooth the image motion even more if desired. Since the set is 240HZ refresh it can of course display 24p correctly without pulldown by repeating the 24P frames just a like a real film projector. The value difference for 60P is if one wants to take a still image from the video file , in that case the 60P has full resolution to use compared to a field for 60i and likely at a faster shutter speed compared to a 30P or 24p file.

Ron Evans

Re: 24 or 30
 

The issue is more on playback. If the TV is a 1920x1080 then it will have to scale up the 1280x720P60. Same applies if the TV is a 720P TV which will have to scale down the 1920x1080 image to fit. Since most new TV's will be 1920x1080 you will introduce less scaling artifacts by shooting for the display resolution. Since one is never sure the real resolution it is likely they all scale to some extent !!! I am choosing to move to 1920x1080 60P for everything I shoot as it is easier to deal with. I don't really like the film look so slow frame rates for me are not appealing as I like smooth motion, as if I am there look. The economies of interlace or slow frame rates make little sense these days of digital.

Ron Evans

Re: 24 or 30
 

Ron,

Are you speaking specifically about natively from your camera to TV? The OP question, or point, was whether 30p could be put on a BD, and presumably, viewed on a BD player. I assumed she would like to shoot in 30p.