Yep, I’m going to do some more experimentation tonight (including DNxHD from the Atomos)… interestingly I just tried re-rendering a short (ungraded) sample off the Vegas timeline to ProRes LT again (I’m using the Miraizon codec), imported it into Premiere and it seems I can still recover the highlights there – so they are clearly not ‘lost’ by Vegas, just not viewable… ?
I’ll have a try with Catalyst as well, but worst-case, it seems like I can just cut it in Vegas then grade somewhere else.