....trouble collaborating with a Resolve user that I need to send files to....What we need to do is...Sending raw files to him, which he makes a rough edit of and sends an XML back and I'll finnish it in FCP...This seems not to be working because Resolve has some issues with A7SIII files apparently. ?
I have an A7SIII, and all codecs from that camera work fine on Resolve Studio 18 and FCP 10.6.5. It's possible your other user does not have a licensed copy of Resolve Studio. The free version of Resolve has some significant limitations, especially particular codecs on specific hardware platforms.
If you want to collaborate using native A7SIII files, he needs to get a licensed copy of Resolve Studio 18.
While it is theoretically possible you could generate FCP proxies and send those to him, Resolve cannot freely color grade an FCP timeline and send back an FCP-readable XML containing those grading changes. E.g., FCP doesn't understand Resolve color effects such as Magic Mask, Color Warper, etc. Also, you normally want full-res files for color grading, not just proxies.
For a one-way workflow from FCP to Resolve, you would do the media organization in FCP, edit a basic timeline minus effects, transitions, etc., then send that XML to the Resolve editor, who both grades and finishes the edit. The Resolve editor would also need the same full-res camera files for grading since he is doing the final export.
For a two-way roundtrip from FCP to Resolve and back, the normal procedure is the FCP editor makes simple, basic edits (no transitions, color wheels, etc), then sends an XML to the Resolve editor who must have the same full-res camera files. The Resolve editor does few or no edits but grades that timeline, then exports an XML *and* new media with grades and edits baked in, then sends that full-res media and XML back to the FCP editor. The FCP editor then finishes the edit, adds titles, transitions, sweetened audio and does the final export. The FCP editor cannot use the original camera files since Resolve must export new media. The purpose of sending the Resolve XML is to allow the FCP user to relink to that *new* Resolve-exported media, not the original camera media.
Any collaborative workflow should be tested on a small scale first.
If any others familiar with FCP/Resolve workflow have other suggestions, maybe they can correct me or add further suggestions. Here is a Ripple Training video that discusses the subject:
"Final Cut Pro to DaVinci Resolve & Back":