That thread link is great to understand the hows and whys but to answer your question simply: 2:3 pulldown (also know as "telecine") is used to convert 24fps film to 29.97 NTSC video. In other words, it adds extra frames that are synthesized from a combination of the original 24 frames to get 29.97 frames of NTSC. If you are not shooting 24p and delivering in NTSC you can safely ignore it.

~jr

Thanks guys!!!!

Deleted.

"Feel free to correct any mistakes. :)"

Since you invited :)

No pulldown is added to film when it is projected.
The projectors do have a two blade shutter so your eyes are flashed twice with exactly the same image to help reduce flicker.

The reason for adding pulldown is to 'fit' 24 frames per second into 60 fields per second. It's a very different process to how film is projected, there's no fields involved. In 24PsF60 some of the frames contain fields from adjoining frames. Removing the pulldown can be quite tricky.

In PAL land film is converted to video in the telecine by running the film at 25 fps and each frame is split into two fields, the pulldown is much easier remove to recover the original frames. Just tell Vegas the source is progressive, job done.

Bob.

No message.

""All the field and frames pull down etc is is to allow the viewer to watch a motion picture ( a bunch of stills) in low ambient light without flicker.""

Quite the contrary. Frame rate is (and was) increased in order to allow viewing TV in HIGH ambient lighting without objectionable large area flicker.

I do not know when the movie industry adopted the double shuttering (2 per frame) in projection for the same reason. Prior to that, movie houses had to be as dark as caves and projection intensity low enough to avoid headachy large area flicker.

I am not aware that current FILM projection has gone up to triple shuttering to produce 72 frames per second.

However, with the new digital projectors you can do almost anything.

As for removing the pull-down effect from 60i video, it is rather easy and it has been done since the birth of digital processing in common digital TV's which tauted progressive scan. All you need is memory and the appropiate algorithm to sort the fields out.