Final Cut Pro 7.0.3 SD field issue

Hi Everybody,

Does anyone could me help with the following issue.
I'm shooting in about 5 different HDs codec but my end copy will be analog Betacam, a already tested a lot of different down conversions log and transfer to SD compressor to SD, BlackMagic realtime hardware downconversion it is the best result but I loose some resolution, all others downconversions the fields like dominance inverted. what workflow do you suggest to get best downconversion for Betacam SP?

Thanks