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Post #143095

Author
GundarkHunter
Parent topic
Questions on framerates in film
Link to post in topic
https://originaltrilogy.com/post/id/143095/action/topic#143095
Date created
29-Sep-2005, 11:37 AM
Films have been shot @ 24fps since the beginning of the sound era. It may have had something to do with Vitaphone synce issues, but I think it was that engineers found they got the best sound quality (of the time) at that frame rate.

Video transfers are done in North America according to a 3:2 ratio. That is, one frame is recorded for 3 fields, and the next is recorded for 2, with contiunuing alternation, resulting in a frame rate of 29.97fps with no noticeable flicker. Prior to DVD, this used to result in some goofy-looking artifacts, but they were only visible in slow-motion. You would have fields interlace that weren't supposed to, and the frame would jitter. DVD has a flagging system built in so that progressive scan displays 'drop' the redundant field. Some problem DVDs have crept through the system, but most are true to what I have said. 3:2 pulldown has its quirks, but generally works well, and is infitely preferable to PAL speedup.