Tue Oct 09, 2018 8:30 pm
I'm on very similar hardware.
Have you made any progress with this issue? I wouldn't expect 4K to render much faster than this, although I've only worked with RED, not Alexa. But in general, DaVinci's going to take shortcuts to get you realtime playback while you're editing, then it slows down to give you maximum quality possible while rendering. You can check "use optimized media" and "use render cached images" in the Deliver Settings -> Advanced tab to get closer to realtime, but the quality will likely suffer. For review and approval of edits, I'll knock down the timeline resolution to a fraction of the desired deliverable, too, which also speeds turnaround.
But if you need optimal quality ASAP, make sure the destination(s) you're writing to is fast. If your source media is on a SAN or NAS, and you've got network rendering set up, you can segment an intermediate render into chunks, spit out 1ofx chunks into a good intermediate format like prores, dnx, or stills. Then combine the chunks to final delivery format. Of course, x is the number of machines you can throw at the task, and if x<2, it won't help.
-MacBook Pro (14,3) i7 2.9 GHz 16 GB, Intel 630, AMD 560 x1
-[DR 17.0 Beta9]