Why does 24F interlace when 30F doesn't?

G

GregJ

Active member
I've shot standard definition 30F before and been pleased with the results. Today I shot 24F. When I uploaded to Final Cut, I got interlacing that I don't get with 30F. I can make it go away by changing the field dominance in the timeline to None, but I wonder if I'm doing something wrong here. Why is there interlacing with 24F and not 30F?

Could it be the capture setup?
 
Dunno, depends on what version of Final Cut you have plus what easy-setup you have. It says in the camcorder manual what the camera can shoot and what pull-down options you have for SD & HDV. I would check that out.
 
In standard definition, the XH A1 records 24p with either a 3:2 or 2:3:3:2 pulldown. The pulldown type is selected in the menu. If you don't want interlacing, choose the 2:3:3:2 pulldown and remove it on capture in FCP. The capture preset should be something like DV NTSC 24p with advanced pulldown removal selected.
 
GregJ:

The Canon A1 shoots progressive (non-interlaced) video when set to 24f 0r 30f. Only the 1080 60i is interlaced. When you import the footage into an NLE you must use the correct program settings or template to match the footage. I use Vegas not FCP but make sure you base settings are as follows:

frame rate: 23.976
pixel aspect: square or 1.000
field dominance or order: progressive or none
frame size: 1440 x 1080 (or set to 1280 x 720) if you want smaller HD files

Never try to deinterlace progressve footage or use and interlaced editing template/settings for progressive footage.

Good shooting, good editing,

S Cannon
 
I edit my HDV in 1280 x 720 mode so I said 1.000 by habit. If you edit 1080i then your editing template is 1.33. Below are some other interesting and hopefully helpful facts re HDV


  • 720p is recorded at roughly 19 Mbit/sec while 1080i records at 25 mbit/sec.
  • In 720p, the luma sampling matrix is 1280x720, square pixel, exceeding DVCPROHD's 960x720 sampling.
  • In 1080i, the sampling matrix is 1440x1080, with 1.33:1 pixels; this is the same luma sampling used in HDCAM and exceeds DVCPROHD's 1280x1080 sampling.
  • Color sampling is 4:2:0 in all HDV formats.
  • HDV uses long-GOP MPEG2 for video, with a 6-frame GOP for 720p and a 15-frame GOP for 1080i.
  • MPEG 1 Layer 2 is used to store 16-bit, 48 kHz 2-channel audio at 384 kbit/sec, with 4:1 compression.
S Cannon
 
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