Curtis: I am not getting that behavior. In order to know what's happening, we need to know how you're doing it.
Are you using in AE the Quicktime export component for Flash (ie, File > Export) or are you adding your Comp to the Render Queue?
Are you exporting with transparency/alpha?
No QT is not installed on my machine.
I am adding the comp to the render queue.
I am not exporting with alpha.
I am not able to reproduce your problem. We may need to discuss more details. For example, how are you changing the output size, then? I mean to go from the DV sized comp to the smaller size?
Stretch on output. Changing the settings from 720x480 DV NTSC to 400 x300. Would I be better off just nesting it in a 400x300 comp?
That did it. Not sure why, but I had to just put it in a new comp instead of stretching.
DV is 720x480 (NTSC). D1 Signal is 720x468. Believe it or not, there are even more "lines" in a broadcast singal than 486.
When you captured your DV source, were the black lines in the source as well (as you view the footage after it has been caputred)?
Or, were they just in your rendered file? If they were in your source as well, it was a result of both how the images were captured, as well as how they were digitized.
This is something I've been battling as well. I've ton a bunch of test renders at different settings over the last several days. I haven't found a fix at all, but I have noticed these couple things:
If you do File/Export/FLV, the 400x300 works fine for me, no matter if I'm using CS3 or CS4.
If you want to export cue points for use with Flash, you MUST use the render queue - which means you can't simply export - which sucks.
Render queue always outputs black bars on top & bottom, unless I change it to 400x293 (instead of 400x300) but even then,
I will still get the bars in some online players.
The whole issue of PAR change from .9 to .91 is irrelevant because you can export FLV just fine, but you can't render FLV correctly.
This points to a flaw in the way the program handles "Export" vs "Render" for this particular output. I wish they would put out a fix for this.