I shoot AVCHD footage from an FS700 and edit and heavily grade natively in Premiere Pro CS6.
I was told that if I convert my footage to ProRes and THEN edit and grade, the colours and details will hold up better than doing so with native AVCHD and will ultimately result in better looking footage.
Here is a quote from the forum to justify that. Please can someone confirm if this is true?
AVCHD is a very compressed and lossy format. Original footage shot in AVCHD will mostly look good, but the trouble begins when you start recompressing the footage. Recompression happens whenever you convert the footage to another format, or whenever you use the footage in an editing environment and you have to render your video.
When you edit AVCHD natively every time you add an effect, title or whatsoever you will lose quality and this will get worse the more generations you make from your original footage. That's why effects, titles etc. are always rendered to ProRes 422 (or higher) in FCP10. Because ProRes withstands multiple re-encoding much better than AVCHD.
When you first convert your AVCHD to ProRes you will get a first generation loss. But the advantage of ProRes is that it is a transparent format, i.e. once your video is in the ProRes format it will not further degrade even after multiple re-encoding. ProRes LT runs at 82 Mbps but that does not mean anything. The LT codec is much more lossy than ProRes 422 and 422 HQ, which means once again that it will not withstand multiple generations. That's why the best workflow is to convert any lossy format to a transparent format such as ProRes 422 and up. You will always lose a tiny bit of sharpness during the first conversion, but from there on you will be safe even when you use the ProRes footage in complex projects with multiple filter stacks.
