I am using CS3, often in 1080i mode. I import Jpegs in my workflow, normally in high res. However, I find myself resizing them to fit the screen once they are in the project. Most of my project exports are to 16x9 standard definition mpeg or WMV. I notice that the photos in those projects do not look as clean as they went in. Is there a suggested approach as to how settings should be, so that imported images such as Jpegs and later exported in an SD Mpeg or WMV format can keep their high quality? Should I be resizing them in Photoshop prior to importing into Premiere? Thank you.
Resizing them in PS is the easiest way. You can batch convert them to you PR project settings. Alternatively you can use scale to frame size in PR. Whatever you do, they will never look as crisp and clean as a 3800x2800 image because you end up with 640x480 NTSC with square pixels.