The file I am importing into Media Composer is an Apple Prores 4444 Quicktime 1920×1080 with an upper field dominance. The film was originally shot on RED in progressive but the online house re exported the Quicktime after the grade with a forced interlace, I think for DVD purposes.
I will be cutting a trailer from this QT and exporting for the web and also for DVD.
What is strange is that when importing files I only have a choice of DNxHD 120,180 and 180X but when I export I have a choice of DNxHD 36,120,145,180,180 X