320*240 export single field on progressive

I don't understand what's going on. I'm using Premiere Pro CS3 for fun, so I'm
not an expert when it comes to formats, framerate, etc. My source files were
originally mpeg type files, but I converted those to DV to work with Premiere.
The whole thing is progressive. Everything works as expected.

But for some reason when using Adobe Media Encoder set to 320*240, field order
set to progressive. But the output looks horrible, like a field was removed.
Thus it looks jagged on lines and flickers a little. Yet, same exact settings,
but at 480*360, it looks perfect. I noticed this with Flash FLV and mp4-h.264
exports.

Take a look:
 <http://premium1.uploadit.org/TimothyB/export_problem.jpg>

First set of images shows the 320 scaled up next to the 480 one, the next set
shows the 320 at default size, but the 480 scaled down to match.

Your in the wrong forum. This forum is for Premiere 6.5 and older.