When you import a file, we do several things automatically behind the scenes.
First, we compress the file to a lower-resolution "proxy" file. This file is exclusive to Cquence, and is only intended for playback inside of Cquence. Any time you export a project, for example to Adobe Premiere, the original full-quality media files will be used.
This has several benefits, including faster upload speed, and the ability to play back and edit files inside Cquence from any machine regardless of where the files were created, though you may need to relink the original full-quality media files when you go to export them.