Question about Premiere Pro's aspect ratio math

[Asterra]

I'm using some DV footage that was recorded as 16:9. Let's do a little math.

1080/480=2.25. 1920/2.25=853.33. So a widescreen DV frame converted to square pixels comes out to about 853x480. Now, 853.33/720=1.185. This means that the correct ratio to achieve a full widescreen frame from widescreen DV is 1.185.

Premiere Pro's D1/DV NTSC Widescreen ratio is given as 1.2121.

What is the result of this? The result is black bars on the top and bottom of my video. And since there doesn't seem to be an option to manually enter a ratio, I'm not seeing a way around this, outside of re-rendering the video externally. And I'll be frank: The need to render raw videos outside of Premiere Pro in order to skirt its shortcomings is beyond old.

I don't really care if Premiere Pro is correctly conforming to some sort of hidden, irrelevant obfuscation. My video is 720x480 and I need it to fill a 1920x1080 frame. Any takers? ;p

[poisondeathray]

Premiere bases it's calculation on 704 width (as do many software and official governing bodies) . If you want to know the nitty gritty details, there a 50-60 page discussion somewhere ...

If you want the "short" version
http://provideocoalition.com/index.php/cmg_keyframes/story/par_for_the_course/

[Asterra]

Right, I figured there was a reason. That's why I tried to snipe it in advance. It's not relevant to my needs. ;p I didn't encounter this issue when I did my original video project because I undertook to conduct the entire ordeal from within After Effects. This time, that is simply not feasible, because I'm having to merge several video sources, each of which possessing eight separate audio channels.

[jagabo]

In a 720x480 DV frame the inner 704x480 sub section contains the 4:3 or 16:9 image. The extra 16 pixels (8 on each side) are padding (though they may contain picture too). So the pixel aspect ratio is:

DAR = PAR * SAR
16/9 = PAR * 704/480
16/9*480/704 = PAR
1.212 = PAR

In a video where the full 720x480 frame contains the DAR (MPEG 2 spec, for example):

DAR = PAR * SAR
16/9 = PAR * 720/480
16/9*480/720 = PAR
1.185 = PAR