The original clips I was working with in premiere were MXF files and the play back was lagging badly so I was told to convert them. I converted the clips through media encoder to Pro Res 422. When i imported these newly converted clips, and went to "reveal in finder" they are still linked back to the original MXF clips and they are still lagging in playback, both in the timeline and in the source monitor. The original MXF files are quite large, some of them being about 27 gb, others being under a gig. I need to be able to edit these clips and the lagging makes it impossible to do so.