Is there a practical difference between NTSC and PAL video files?

I'm making an interactive educational CD for my client.  It's a study guide for a documentary film.   The film, on a companion DVD being prepped for both the US and European market.  Each market gets a different DVD version, ie NTSC or PAL. That disc will be for playback on both a DVD player and computers.

My intention is to create one Educator's Guide disc that can be used in both markets (for  use on computers only -- no zone problems or compatibility issues).   The Ed. Guide will have .mp4 clips from the documentary film itself (as well as various documents and photos)

Does it make a practical difference if I request that the .mp4 files being delivered to me are "NTSC format" or "PAL format" ? My understanding is that when it comes to computer playback there is no practical difference between the two formats.

If I request "PAL compatible" files do I get more vertical lines of video?

If I request "NTSC compatible" files will I get black bars at the top and bottom of the screen?

Comments

  • Triem23Triem23 Moderator

    NTSC has a 29.97 frame rate and  accepted dimensions of 720x480.

    PAL is 25 fps and dimensions of 720x576.

    Both dimensions given are for 4:3 aspect ratio. For 16:9 there are multiple solutions. 

    These are real differences and will need to be accounted for.

    Since you have two output resolutions, you'll want to work at a higher resolution (720 or 1080 vertical resolution) and downsample to create your masters.

    Hitfilm doesn't have interlaced output. DVD at 25/29.97p will be interlaced... Solution?

    If you're editing in Hitfilm, think about editing at 59.97p. For NTSC each frame will become an interlaced field. For PAL you'll have extra frames for telecine.

    Another option is to work at 24p for NTSC then speed the footage up to 25 for PAL. This is typical for DVD of films, but can cause the audio to go a bit "chipmunk."

    This is a genuinely complex topic and suggest some Google work. PAL/NTSC conversion is a pain. 

  • Grateful as always --

    This Ed. Guide disk is for non-broadcast classroom use on a computer screen.  I'm not doing the conversion, just the UI/interactive coding.   The video is being created/edited in PAL.

    If I had to pick one video format to give classroom viewers the best experience, in both the US and PAL markets, which would you recommend? 

    I'm okay with google research and reading up on topics to get smart -- I'm less confident making a final decision based on limited experience.  These are mp4 video files -- they will play perfectly internationally -- I'm just not sure which video package gives a better computer viewer experience -- NTSC or PAL -- 

     

  • Triem23Triem23 Moderator

    Tough call. Default computer refresh rates are tied to the voltage of the host country. NTSC monitors default to 60 Hz--the rate of North American wall current alternation--and PAL monitors default to 50 Hz--European wall current alternation.

    So the frame rate issue is a bit of a pain. Still, if the disc will be played back on a computer, not a TV, I'd say don't stress too much. Computers, unlike TVs will try to adjust playback rate and monitor refresh. So... Guest tutorials I've done for FXHOME are created at PAL standard 25 fps. My Hitfilm University tutorials are created at 24 fps. I'll bet if you were to go on YouTube and play any FXHOME tutorial followed by a Hitfilm University tutorial they'll both look fine.

    It's for PC, so you can work progressive (yay, no interlacing!) since the primary video is being shot and edited in PAL, just work at 25fps and don't worry about it. You'll want a consistent frame rate across the entire project, but, if someone else is doing US localization, it's not your problem. And, again, computers are better at adjusting to variable frame rates. Especially discrete AMD and Nvidia cards, both of which have specific functions to synch a monitor with the frame rate of a game or media clip.

    If you were actually going to broadcast, Blu-Ray or DVD you'd have to worry about frame rates and different formats, but, for general computer use, no problem..

    Also, different pixel resolutions only apply to STANDARD DEF NTSC/PAL. HD video is 1280x720, 1920x1080 or 3840x2160 on both sides of the pond. I'm sure the initial video will be 720p or 1080p. Either works, so just do your stuff at 25fps and find out what resolution they're shooting/editing at and match it.

    No, wait, I lie. You DID say there's a DVD version. Talk to your editor. Since Hitfilm doesn't output interlaced you might want to do Hitfilm work at 50 fps. Then, when making the DVD each frame will get chopped into a field (for correct interlacing), while the computer version can be left at 50 fps or quickly re-rendered at 25 fps to save file space.

    For DVD I'm still assuming footage is being shot and edited at an HD or FHD resolution. Great, the DVD encoding software should be able to handle the downsampling for the DVD, so you probably won't really need to worry about the different NTSC/PAL resolutions in SD either. Downsampling is always easy. Upsampling is the pain. 

    Btw, if you're in Hitfilm 2017, remember you can fill the Export Queue with timelines from multiple projects. So, you can maximize your "front of computer time" editing and set up multiple timelines/projects to render overnight. 

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