Trying to understand proxies, so I apologize if this seems like a stupid question.
I'm working with these 4k RAW files shot on the Arri AMIRA (Apple ProRes 4444)
I import my files and while it imports Premiere creates proxies that transcodes the files to 1280x720 ProRes 422 (Proxy).
I lay my 4k files onto my 3840 x 2160 sequence. The files show up full res and playback is very choppy. After my proxy files are done, I toggle proxies on in my toolbar and my proxies begin playing. Playback becomes very smooth. But here is my question.
When I toggle my proxies on, shouldn't I be getting black lines around my image because it's 720p footage in a 4k sequence? In this scenario, I'm not and I'm not quite understanding why?
Not that I'm complaining. I prefer for the 720p image to take up the full screen. Just wondering why it does that?