Pulldown

[naavt]

I know that this have been throughly debated in dvxuser but no matter how many technical pages I visit about this matter some doubts still cloud my mind.

I've been shooting interlaced all the time (I mostly do Docs so I didn't missed progressive footage yet), but I'm willing to learn a bit if you all could help me. So...

1st - Why is it called Pulldown when it really adds something to the original footage? For what I can understand, if I have 25fps (in a PAL based country which I'm living), I end up with a somewhat interlaced footage because I'm multiplying the original 1st on 2 frames, and the original 2nd on another 3???

Why the heck do I want to do this if I can shoot interlaced and end up with something similar than the above situation? Just because motion is depicted a kind a way more like 24fps film footage?? Even if it's so... I read a lot about jerkiness and judder on that kind of footage! Why do people sacrifice motion smoothness for the sake of motion "like film"?

2nd - If in the end my movie is to be seen on a digital system, like transferring it to digibeta for Festivals and so on, what is the major benefit of shooting progressive if my footage will end up showing on a interlaced system???

3rd - Even then, I'm willing to give it a try and see the results. I have a XH-A1 that shoots 25F (which I've been told that it has about 20% less resolution than 50i !!!), so can any expert be kind enough to point me in the right direction on how to import and treat 25F footage?

Thank you all for this.
Regards

 

[Cranky]

1st - Why is it called Pulldown when it really adds something to the original footage?

http://en.wikipedia.org/wiki/Telecine#2:3_pulldown

For what I can understand, if I have 25fps (in a PAL based country which I'm living), I end up with a somewhat interlaced footage

http://en.wikipedia.org/wiki/Telecine#2:2_pulldown
http://en.wikipedia.org/wiki/Progressive_segmented_Frame

Why the heck do I want to do this if I can shoot interlaced and end up with something similar than the above situation?

To have "film-like" jerky motion and full vertical resolution instead of having fluid "real life" motion with halved vertical resolution.

2nd - If in the end my movie is to be seen on a digital system, like transferring it to digibeta for Festivals and so on, what is the major benefit of shooting progressive if my footage will end up showing on a interlaced system???

It is much easier to stuff progressive into interlaced, than the opposite. Your 25F will be stuffed into 50i and, if all is well, treated as 25PsF.

3rd - Even then, I'm willing to give it a try and see the results. I have a XH-A1 that shoots 25F (which I've been told that it has about 20% less resolution than 50i !!!), so can any expert be kind enough to point me in the right direction on how to import and treat 25F footage?

25F is native progressive. Treat it as you would treat any other native progressive footage. Its vertical resolution in progressive mode is about 20-25% less than resolution in interlaced mode IF YOUR SUBJECT DOES NOT MOVE. The vertical resolution is still higher than resolution of a single field, the camera does not simply drop one field to produce 25fps like the Sony Z1 does, there is more black magic inside. For all practical purposes it is native progressive. With about 700 lines of resolution it is on par with pixel-shifted Panasonic cameras.