60p vs 60i video quality

Joe,

1080 60i = 60 1920X540 interlaced fields per second recorded/interlaced onto 30 1920x1080 frames per second. Since two 1920x540 fields taken 1/60th of a second apart are recorded/interlaced onto one 1920x1080 frame, there will only be 30 1920x1080 frames per second.

Since field 1 contains only the odd lines (upper field) from the first image this is why it only has 1920x540 resolution and field 2 taken 1/60th of a second later contains only the even lines (lower field) from the second image and both fields are recorded/combined/interlaced onto one 1920x1080 frame.

How interlacing works: http://www.neuron2.net/LVG/interlacing.html

You can see progressive is way better than interlace. A Mac with an i3 and better processor will have no problem playing back 1080 60p videos smoothly. For older machines, it's easy to downsize the 1080 60p videos to 1080 30p, 720 60p, or 720 30p with NLE, but archive the 60p AVCHD source for future use.

Uploading 1080p videos to YouTube, the site will automatically prepare 1080p, 720p, 480p, 360p, and 240p resolutions so people with older computers can easily choose a resolution appropriate for their machines. Since YouTube doesn't support 1080 60p yet, just convert 60p to 30p and upload.

Joe,

I finally got around to create some samples to show the downside of shooting 60i when your camcorder can shoot 1080 60p.

Deinterlacing will never produce the same image quality or smoothness as shooting progressive at the first place.

When a 1080 60i clip is added to the timeline and then "Shared" (exported), FCPX will default output a 1080 30p .mov (or .mp4) video like this:

The upper 1920x540 field is used and the lower 1920X540 field is discarded, losing half the resolution and 30p will never be as smooth as 60i or 60p. The lines of the upper field are doubled to fill in the gaps, resulting in heavy aliasing around the edges. The results are acceptable but will never be as good as shooting 1080 60p.

Doubling the data rate will improve the picture but not if you're doubling the frame rate as well. Data rate is punt per second. You need a higher amount if you're generating twice as many frames.

You should check the fields in FCP with both fields visible in an area of motion to make sure there are no fields. If there are fields Compressor is not processing the material properly.

my thoughts on i or p from me with some illustrations:

https://sites.google.com/site/karstenschluter/i-or-p-this-is-the-question

in a few words:

i feels 'smoother' due to the forced blurring on final display.

but p is 'better' if done correcty (asks for cinematography skills/unrderstanding)

Avoid shooting interlaced videos!

I work in the entertainment industry and only shoot 60p to be displayed at 60fps for maximum smoothness - not for slow-motion playback.

Shooting 24p or 30p: 1/60sec or slower shutter speeds must be used to introduce motion blur to lessen, not eliminate, the choppy appearance. Shooting with slow shutter speeds under bright sunlight, ND filters are required to control depth of field and to prevent sensor dusts from showing up prominently at F11 on up.

60p: Since 60fps videos will turn out smooth even with shutter set well above 1/60sec, Aperture Priority can be used to control depth of field under bright sunlight without an absolute need for ND filters. Filmmakers - James Cameron, Peter Jackson, and George Lucas - have all produced 60-frame-per-second projects when they are not required to shoot 24fps - Avatar 2 & 3, King Kong Universal attraction, and Star Wars Star Tours attraction - because they believe 60fps delivers a more lifelike and immersive experience.

Once again - avoid shooting interlaced videos!

I always shoot in 720p 50. The reason is as you named is I like to to do slow down now and then, and more important do smooth pan and tilts. The other option is to shoot in 25 or 24. What is the benefit of shooting in the 25 mode insted of 50. I mainly deliver my video to you Vimeo.

Some more explainations:

1080 60p = 60 1920X1080 frames per second - the smoothest and the future of HD video.

1080 60i = 60 1920X540 interlaced fields recorded on 30 frames per second - half the resolution.

1080 60i can also = 30 1920X1080 frames recorded in 60i progressive segmented frame format - how many consumer AVCHD camcorders and digital cameras record 1080 30p.

Apple TV, YouTube, and Vimeo WILL eventually support 60p videos in the near future since more and more cameras shoot 60p!

Vimeo 1080 60p group: http://vimeo.com/groups/native1920x108060pclips

By the way, the latest iMovie and FCP already can output 60p videos and the newer Adobe Flash Player can play them smooth from the internet on the newer computers.

"1080 60i = 60 1920X540 interlaced fields recorded on 30 frames per second - half the resolution."

This is a misrepresentation. It's not 1920x540 at 30fps, but 1920x540 in 1/60th of a second. 1920x1080 in 30fps.

The current delivery for no devices even Blu-ray supports 60p. You can put 60p on the web and probably half your viewers or more will get stuttering playback or long downloads or caching delays.

Your choice: produce for what's deliverable now or for what will be deliverable in the future. Personally I prefer 720p30 for production for web delivery.

What application are you using Joe? In the viewer set the appearance to show both fields.

Therefore when the 30p footage is of a fast moving object, your saying it doesn't look as good due to it doesn't have the interlacing working for it anymore. Is that correct?

Basically. It varies. It depends on the content and the format and the camera and all the factoprs that go into compression. There is absolute on how well it will work. It's very much dependent on the content and camera. Low light with a lot of noise in the image, the field blending can look much worse and appear as pixelzation. High resolution, well lit, well comrpessed, not too much motion, and it'll look fine.

That's what I thought might be case. This is the FCPX forum. Some of what's in this thread (including what I wrote) doesn't apply to your product. You should address this on the Final Cut Studio forum.