23.976 vs. 29.970 NTSC Captures

[Benihana]

Hello, I've been searching the forums for a while now, and I can't seem to find adequate information about a question I have. I am trying to make some quality encodes to be played on the computer, as well as burned to SVCD via TMPGEnc. I was capturing at 512x384, then learned that with NTSC, it is best to capture at XXXx240 or XXXx480. I decided to move onto full NTSC captures at 640x480 but my system drops frames too frequently, so I am trying to learn how to capture at 640x480 but still maintain a good frame rate and adequate frames. Here are 2 possible setups of mine:

1:
640x480 @ 29.970
44.1 KHz PCM Audio

2:
640x480 @ 23.976
44.1 KHz PCM Audio

With setup 1, I usually get about 14 dropped framed per 5 minutes, and with setup 2, I get 0 drop frames per 5 minutes. I'm leaning towards the second configuration, but what will be the drawback of capturing at 23.976 instead of 29.970? I know that 29.970 will work when converted via. TMPGEnc to SVCD, but I'm not too sure how 23.976 will come out on SVCD. Any clarification would be most appreciated, and also, I am not sure if this goes into the Newbie section or not, as under the Newbie section is says "If you're new to DVD ripping please post your questions here." (which I know fairly well) I'm just basically looking for differences in 29.970 and 23.976 captures, and will they both work well on SVCD playback, because they will work good on the computer regardless of framerate, but it's the TV I'm concerned about. Thank you. :)

Hardware:
crappy eMachines MOBO (VIA KT133 chipset) with Athlon XP 1600+
512MB PC133
Capture: (PCI) LifeView 3000 FM
Display: (AGP) nVidia GeForce 2 MX 400 with 64 MB
Promise Ultra 100 TX2 Controller Card
5400 Western Digital 40 GB with OS (WinXP Home)
7200 Western Digital 180 GB for capturing

Software:
Capture: iuVCR
Sound Adjustments: Sound Forge 7.0
PCM -> MP3: BeSweet
Video Filters/Editing: Both GKnot and VDub to see which results are better

[trevlac]

Can you do 480x480 at 29.970 ?

That's what I'd try.

Your source is 29.970 Frames per second, so I'm not really clear what lowering the frame rate does. It probably just throws away frames (which is not a good thing for video source).

What codec do you use for the video? You should also use YUY2 vs RGB.

[FlimsyFeet]

23.976 fps is not a "real" framerate, it's what you get when you IVTC a 29.97 fps video interlaced with 3:2 pulldown back to progressive frames.

There is no such thing as a 23.976 fps SVCD.

[Benihana]

I use YUY2 huffyuv codec.

So... You cannot use 23.976 I take it, it MUST be at 29.970 fps. I was thinking of capturing at 23.976 and then doing a IVTC on it to get it going at 29.970, but now that I think about it, I don't think it will work out. I guess I'll try lowering the resolution then. I'll have to resize the 480x480 to a 4:3 resolution, correct? Thank you for y'alls' help.

[jggimi]

Benihana: see www.doom9.org/ivtc-tut.htm for lots of info on Telecined content, and Inverse Telecining (IVTC). It's DVD2AVI/AviSynth focused, but should help clarify your confusion.

If you are capturing Telecined content, you will be able to use it at 23.976, but only after IVTCing during post-processing.

[Benihana]

In case somebody stumbles upon this thread, let me offer an update.

After reading the link posted by jggimi and just experimenting, I've learned that the capture still needs to be done at 29.970 as that is the fps it is broadcasted at. However, since the material is telecined, I can use IVTC to give a post-processed result of 23.976 fps.

Ultimately I ended up upgrading my hardware as my old rig was dropping frames too frequently. Now I capture at 29.970 with huffyUV lossless, and all is well. :)

[Ghitulescu]

What do you capture? It is most probably analog NTSC which is 29.97, telecined or not, it doesn't matter now. So use 29.97i with x480 and a capture window of your intended target, for SVCD it should be 480.

SVCD is interlaced so you can keep the capture as it is.

[zilog jones]

One would assume he's not making SVCDs any more :)

[Benihana]

Ah, no it was cartoons I used to capture at that time. An analog NTSC source. Today I don't capture straight off of the tele anymore. I mainly use it to capture old home videos to preserve them.

Haha, and yes. I'm not making SVCDs anymore. :) I don't really do DVDs much either nowadays. With a straight connection to the TV via HDMI, it's much easier to just play it directly. Couple that with a PS3 Sixaxis controller, I can kick back and watch in peace. :)