At most of the time I shoot my footage at Cinestyle picture style and sharpen and colorgrade it afterwards. As I have seen so many times in several clips it that if you add the sharpen effect to your footage you well get a border around your video. Normally I would always set the sharpening to 30 for DSLR footage. This works great and gives a great result.
The weird border as you can see above is a known bug in Premiere CS6. Might get out it a online casino club later bugfix but for now we have to use the workaround. There are two work arrounds that you could do:
My suggestion is to use the Unsharp mask cause itâs more easy and will give the same result in the end production.