My version of final cut pro is suddenly having a problem, when i capture footage it looks fine, but when i put it on the time line it loses quality, but when i export it the qualities fine again . is there a reason that it does this on the sequence/timeline ?
FCP lowers the quality of the image in the Viewer and Canvas to ensure smooth playback, without dropping frames. These small "windows" are to be used ONLY to see your footage to make editing decisions. They are not to be used to judge the quality of your image. This is true of FCP and Avid and Adobe.
As Michael said, if you want to see your footage in full quality as you edit, you need a capture card and monitor to view the footage on. And by monitor, we mean TV or broadcast monitor, not computer monitor.