Originally Posted by 2Bdecided View Post
....It will never be worse (unless your HD camera is worse than your SD camera, or unless you do lousy downconversion in your NLE), but it's future-proof, and looks far better on YouTube than native SD ever can.
Cheers,
David.
Indeed, utmost importance should be given to downconversion from HD to SD. My initial experiences doing this with the default settings in PremiereProCS5.0.3/AME for creating DVD elementary streams off the AVCHD timeline created clips with horrible jaggies, unexplained thin black borders top/bottom or left/right, chancy ways of figuring out correct field sequence, etc. Exporting via Debugmode>AVIsynth>CCE-basic/HCenc has always saved the day.