Blur/motion/ghosting lines on video? How to fix

[Robert James]

Originally Posted by David Jimerson

The frame rate and p or i are not the same thing. Progressive means full-frame pictures are taken. Interlaced means half-frame pictures are taken, the half being every other line of vertical resolution (line 1, line 3, line 5, etc., then the next picture would be the even-numbered lines).

A few points:

60i is often called "30i" or "29.97i," because the time code is based on 29.97 frames per second, but it's inaccurate, misleading, and confusing. It's a throwback which is no longer necessary.

60i is more properly called "59.94i." This is because there are actually 60 (59.94) pictures taken per second, not 30. Each interlaced field is a separate picture. They say two fields put together make a "frame," but anyone who's worked with video knows why that isn't true -- you'll see the comb artifacts made by mashing together two pictures taken at different times.

This matters to the motion, too, because a moving object is in twice as many positions per second as it would be in true 30 fps. True 30 fps would be 30 pictures per second, meaning there's twice as wide a gap between the positions of moving objects from picture to picture. Obviously, less of a gap means smoother motion, so 60i motion is twice as fluid as 30p.

So, you can see why 60i and 60p would have the same motion -- it's the same number of positions per second for any moving object. 60p being progressive, the resolution of a 60p frame is twice that of any 60i field, but the motion characteristics are exactly the same.

There really is no such thing as 30i or 29.97i -- no format shoots or displays 30 interlaced fields per second. But, you'll still see that nomenclature in legacy equipment and software with a history going back more than a decade. Would be nice if it would go away, because it's confusing.

Jeez, if I wasn't confused before. :p

So, basically, if I shoot at 24 fps I should choose HD 1920x1080 24p in the timeline and 24 fps (FILM) as the frame rate in my time-line?

When I render I should render (for the internet SONY AV) I should choose 920x1080 24p with a frame rate 23.976, progressive? For DVD I choose DVD architect.

Each should, then, be selected at Progressive scan.

That seems to be what I am getting now.

[David Jimerson]

Yes, use that timeline for your 24p footage. But no, don't choose 24.000 for the frame rate, choose 23.976.

The frame size for rendering out depends on what you're doing, but 23.976 progressive is pretty much always going to be your frame rate.

[Robert James]

I have also been using:
/ PIXEL RATIO at 1,000 / BITRATE 2,000,000

Is this about right?

[David Jimerson]

The PAR is correct. Bitrate depends on what you're doing with it.

Generally, the render templates are optimized for the purposes they're named for.