So I had a week long shoot that got transcoded last week down to SD (center punch from 4k HD files) using the .9 fit height setting to 720x486 Uncompressed 10bit QT files.
Everything looked right, and processed quickly BUT big motherfucking BUT. . .
I get a call today asking if we transferred Anamorphic!!!! O holy fuck sure enough I looked in final cut (with correct pixel aspect ratio) and everything looked like it came out of a spaghetti western. After some fiddling it looks like RED's ".9 fit to height" is actually doing a PAL pixel correction. IE if I change the clip to "pal CCIR 601 " in FC everything looks fine except its not tall enough to cover NTSC so there is letterboxing NOT WHAT THE CLIENT WANTED. Now I'm stuck re-rendering everything SQ pixel and passing it through a conversion to make it CCIR 601.