Hi to all, my problem is i think

is im not sure the exact settings required when you import avchd.Do you go into project settings before you import into timeline to keep all original settings of video,how do you change setting to keep best original quality in project settings. Basically all i want to achieve is to import my avchd footage into timeline, add transitions,fades, but still keep all original quality,then burn to bluray.
The result after burning is poor picture than the original(even when resampling is set at best)
I have used pinnacle studio 11 and quality fine when burned to disc.
I would be grateful if anyone can point me in the right direction from start to finish.