Aspect ratio

[kippard]

Someone is making a motion graphics sequence for me with JPGS, which are square pixels I believe. He wants to know what aspect ration I want and I told him I want a file for my DV project, non square pixels I believe. He says this is not enough information. Can't a DV NTSC file only be one specific dimension or aspect ratio? He says I must tell him the aspect ratio I want the project in, in square pixels. What is it? Can someone shed some light here for me? THANKS AGAIN Videohelp! kippard

[guns1inger]

For fullscreen (4:3) NTSC, the square pixel equivalent is 640 x 480. For widescreen (16:9) it is 854 x 480.

That said, he should be working in correct NTSC resolution (720 x 480) with non-square pixels until the output stage to ensure correct display when you incorporate the work into your video.

Is there a reason it has to be provided as jpegs ?

TGA or even TIF would be preferable, as an compression would be lossless (as opposed to jpeg), or even better, a losslessly encoded video file if there is no alpah channel required.

[edDV]

If this is a video project, what editing software are you using?

Photoshop CS, Premiere and Vegas will all manage square pixel scaling to 720x480.

For SD 4:3, 640x480 gets H stretched to 720x480 or 720x540 gets downscaled to 720x480. Downscale is usually better for quality.

For SD 16:9, 854x480 gets scaled to 720x480.

Using software like above, it is possible to import graphics and stills in HDTV (or other) higher resolutions and let Premiere or Vegas manage the downscale. You need to test this option with samples and compare to the above.

I like to prepare graphics at 1920x1080 (square pixel) so I have a HDTV compatible master for the future. Then I let the edit program or Photoshop downscale to 720x480.

This method also works for odd sizes like the 2592x1944, 2048x1536 and 1600x1200 sizes put out from my Canon S-60 still camera.

[kippard]

I don't know what app he is using and usually this stuff doesn't come up because like you say the app sorts it out, but I will tell him "4:3 NTSC, square pixel equivalent 640 x 480 for our NTSC resolution 720 x 480 with non-square pixels project" Correct? Thanks!

[edDV]

I don't know what app he is using and usually this stuff doesn't come up because like you say the app sorts it out, but I will tell him "4:3 NTSC, square pixel equivalent 640 x 480 for our NTSC resolution 720 x 480 with non-square pixels project" Correct? Thanks!

Yes 4:3 720x480 is what you want but I would create the originals at 720x540 (square pixel) or above so that you don't have to expand 640 to 720. Expanding lowers quality. Downsizing vertical from 540 to 480 will be better for quality.

[kippard]

Thank you!