I've read just about every post on the COw about HD to SD techniques, of which there are many.
I tried downconverting EX3 originated color corrected ProRes HD 422 to SD 422 using just about every available software (& 1 hardware) technique. Compressor with all the variations, After Effects w/wo preblur of the HD image, scaling in Nuke, outputting from Kona3 to LHi (in a computer to computer HDSDI loop), post sharpening, noise reduction algorithms, etc. All of them look unacceptable and not like you'd expect like good, crisp SD Digibeta footage. I realize the HDCAM/SR deck downconversion method is the best, but on a 60+hour sources, not cost effective.
SO, with these multiple variations, I've test encoded in Sorenson Squeeze 7, Episode, Bitvice, Compressor, and Main Concept Reference. All look lossy, unacceptable. And I think it's the source file which is the real issue: the downconvert is not crisp enough.
So, I'm wondering if the Cinema Craft MP plugin for Compressor is the solution. Feeding it the original HD and doing multiple passes. But as a novice encoder, monkeying with GOP structure, and all those higher brain function controls may not be my strength. Anyone care to chime in on a possible solution?