Aspect ratio discrepency

A

alan b

Active member
As a last gasp before we finally jump into HD, we have been messing around with the DVX's squeeze feature in obtaining a 16:9 format. For whatever reason we hadn't until now. The results I'm getting are due to a combination of the camera, Final Cut Pro, Compressor and Quicktime so I was unsure where to go with this. But I figure it all started with this DVX work-around so I came here.

For one, is the squeeze effect really accurate? After brought a clip into a 16:9 anamorphic timeline in FCP it looks okay in the viewer window but on output (QT movie) it looks a touch stretched horizontally to me.

But the big question is in regard to the actual pixel count. When I output a clip via Compressor I have this basically 16:9-looking frame. If I open it in QT X and open the Inspector, I'll drag the frame out to 1600 pixels and the height comes to 900 pixels (in other words, 16:9, but again, kinda looks stretched to me). But if I open it in QT 7 (which I have as a Pro version for its various functions) and I drag the window out to 1600 pixels it's only 880 pixels tall.

Why would that be?
 
DV 16:9 is slightly wider than true 16:9. That's not because of the DVX; it's DV in general. And DVD.

The pixel size is 720x480, with rectangular pixels which are wider than they are tall. If it were square pixels, it would be 853.33333333 wide by 480 tall. (That's assuming NTSC; in PAL it's 720x576 and the square pixel equivalent is 1024x576.)
 
I'm sorry David but I can't make sense of what you're saying ...

720x480 can be used to make a 4:3 image if the Pixel Aspect Ratio is .9, 720x480 makes a 16:9 image if the PAR is 1.2 ...

Now I don't have a DVX camcorder, but I did use a PD150 for some years and it used the proper math to give me the results I want, as did any of the 'widescreen' DVDs I rented. There is no reason why it can't be done right -- is there? PAR settings start in the camcorder and must be continued in post, but correct is correct ...

Cheers,
GB
 
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