relinking new clips distorts image
Hello Final Cut Wizards!
I have a project that I'm working on for a client, and the previous editor did several things incorrectly which I am trying to fix. The timeline sequence settings didn't match the clip settings, and the footage was never converted from H.264 mov to Pro Res. I have converted all the footage to prores and made a new timeline sequence that matches the converted clips. My hope is to not have to rebuild the entire timeline from scratch. When I erase some of the old clips I can relink their corresponding new converted clips. HOWEVER, when I do this, either the aspect ratio of the new clip is messed up, (ie shows up smaller in the canvas and viewer, or with black bars on the top and bottom, and sometimes the video itself is flattened in its aspect ratio.) and it needs to be rendered constantly (just like when the original h.264 clips were in use).
Does anyone have any ideas on why this could be, or how I can still use the sequence project plan without rebuilding it?
Thanks!!
MacBook Pro, Mac OS X (10.7.5)