What version of Premiere Elements are you using and on what computer operating system is it running?
HDV is 1440 x 1080 HD anamorphic 16:9
(this means that the 16:9 flag stretches the 1440 x 1080 4:3 to 1920 x 1080 16:9 for display after encoding.
The project preset typically for that is
What is the project preset that you set for your original project? If you do not know, please tell us what you see under Edit Menu/Project Settings, General and the readings
for Editing Mode, Timebase, Frame Size, and Pixel Aspect Ratio, even if the fields look grayed out.
A major role of the project preset is to direct the project to establish the Edit area monitor space corresponding to the format represented by the project preset.
You are going to have a 1920 x 1080 space in the Edit area monitor whether you use a 1440 x 1080 HD anamorphic 16:9 project preset or a 1920 x 1080 16:9 project preset.
So, it is not apparent where your black borders are coming from without the requested details.
Am I correct in assuming that all that we are discussing now is how the video is displaying in the Edit area monitor?
You are not talking about export settings yet. Is that correct?
We will be watching for your follow up.