Mixing 50i and 50p

[bosiwollig]

Hello,

I don't know if this is the right place to ask, but I'll give it a try.
I have a little question

I've made some videos with my camera in 50i and with another camera I've made videos in 50p. I want combine them into one project. Which framerate should I select to get the best result? Are there any downsides mixing 50i and 50p ?

Thanks you

[David Clarke]

What frame rate is your final result? If you want a 50P final result then I would edit at that. If you want a 50i result - maybe a Blu-ray at 1920 50i because you can't make Blu-ray at 1920 50P - then edit at that.

If you start a project at 50P you can't change it to 50I and Vice-versa so it is important to get it right in the first place.

I have found EDIUS to be very good at converting the footage either way (50i to 50P or 50P to 50i) which it will do automatically just by putting the clip on the timeline.

[bosiwollig]

Since most of the videomaterial is 50i, I think i will go for a 25p over 50i setup. Is this a good idea?

[createmedia]

Lower frame rates are ok but won't support a medium speed camera pan without appearing stuttery.

50i was developed to give smooth movement of sport on TV, although film types actually like it stuttery on movement hence all the argument about the Hobbit when it was shot at 48p they claimed it looked too clinical.

50i is twice 25p but each picture frame is called a field (2 fields = a frame) and only contains half the displayable lines, 1,3,5,7 (odd field) and then 2,4,6,8 (even field) and is a method of generating twice the information from the source against time or generating an interlace - hence the i after 50.

The eye of course is too slow to see all this happening. But in 50i and if in Edius you select the pause field to frame on a pan shot, you will see the combing effect on the vertical edges in the shot. This demonstrates the smoothing effect on motion this has. 50p is the next step up where the fields are replaced by a full video frame, and thus gives the best quality, but not all devices can display it, and broadcasters still like 50i delivery.

So for the smoothest motion in the most compatible format choose 50i, noting of course that computer monitors are 60p so they tend to de-interlace the video.

As David says usually this is ruled by the delivery point, YouTube or DVD or file. It also depends on the shutter setting on the original camera too.

I facilitated students to make this as part of work experience so here is an event promo made in Edius and as a test I uploaded in 1080 50p just to see what happened

https://www.youtube.com/watch?v=6dZKfqTFImY

The material at 4'06" was shot at 25p and the runners going across the camera appeared to jump from one position to the other when stepping through frame by frame on the timeline, which did not occur on any of the 50i material.

Mike

[David Clarke]

The more frames you film the better the slow mo. I recently tried to slow mow some 25P hand held footage of a football match and the results were terrible - in every program I tried. 50i or 50p slows better.

I recently started filming using a Panasonic GH4 at 4K and I love the pictures but it does now make me want a 4K camera that films at 50P - and at the same price as the Gh4, of course! Needless to say they don't exist. But it explains why sometimes, even though I can film in 4K I use the Gh4 in HD at 50P instead.

[antonsvideo]

what does the scaling quality look like in the GH4 when using 1920 50p?

when I switch my GH1 to 1280 50p (no other 50p or 50i available), the diagonals look like stairsteps, unusable

[David Clarke]

Do you mean in the camera or in EDIUS?

[antonsvideo]

Do you mean in the camera or in EDIUS?

in EDIUS in a 1920x1080 50i project

[bosiwollig]

I have no idea for export settings

Hello,

I shot some video with two cameras, One camera shot at 50i and the other at 50p. I created a 25p project. And now i want to export it. Should I export it to 25p over 50i?
I have really no idea, I know the one is interlaced and the other is progressive. But I don't really understand the difference.


I've heard that bluray doesn't support progressive content (except 24p), so you had to wrap it in an Interlaced container. So I think 25p over 50i, isn't that bad since my project is a 25p project.
Or am I missing something?

[antonsvideo]

you should have started a 50i project, forget 25p (unless you only produce for web)

but 50p is ok for Blu-ray if you use 1280x720