fcp.co logo transparent
fcp clapperboard
Welcome, Guest
Username: Password: Remember me
14 Nov 2020
Moving over to a new system, we couldn't take the old avatars - so please upload a new one!
  • Page:
  • 1

TOPIC: FCP not using render files for export

FCP not using render files for export 09 Jan 2021 15:04 #111995

  • peteramwiggins
  • peteramwiggins's Avatar Topic Author
  • Offline
  • Administrator
  • Administrator
  • The Administrator :)
  • Posts: 771
  • Karma: 10
  • Thank you received: 384

Is it me or am I seeing longer render times because I think FCP is no longer using the render files for export? 
Maybe it has been like this for a couple of versions?


Please Log in or Create an account to join the conversation.

FCP not using render files for export 09 Jan 2021 20:09 #111997

  • joema
  • joema's Avatar
  • Offline
  • Platinum Boarder
  • Platinum Boarder
  • Posts: 1775
  • Karma: 27
  • Thank you received: 395
I've seen a few people report non-use of render files on export, allegedly unique to new FCP versions. However they provided insufficient details to independently verify.

From my limited testing thus far on 10.5.1, it seems to work about like prior versions regarding render cache optimization on export. However the whole render file issue is complex with many variables. There could be additional cases where it's gotten worse, or maybe it hasn't and we just recently noticed.

In Jan 2020 I had a very heated debate with Pro Apps escalation support about this, who after discussing with product support management and FCP engineering, decided it was not a bug and they do not guarantee any specific cache file behavior regarding render or export performance.

They forcefully stated that render files do not improve export performance. There was no possible misunderstanding as I made them repeat it back several times. I referred them to your article:  www.fcp.co/final-cut-pro/tutorials/2177-...-speed-up-the-export

They said that has no bearing on the matter. I then kept them on the phone and walked them through a replication procedure, and had them tell me the # of seconds to execute each case. They could not deny render cache files improved export performance. 

They then said that any observed render or export performance optimization (or lack of it) due to render cache files is not documented and they will not address it.

I followed this up with a detailed email to them summarizing that discussion and including a simple replication scenario.

Since then I've been meaning to revisit this, but it would take several days of testing to re-verify the current behavior across many scenarios. It seems quite complex and involves certain combinations of certain effects (whether built-in or 3rd party). My gut feel is it may involve FxPlug 3 architecture and how that interacts with the render system. That is currently being replaced with FxPlug 4 but it will take a while. I'm not confident they would act on any additional enhancement request, but maybe I'm just being negative.

See my posts in these threads for more info:



Please Log in or Create an account to join the conversation.

  • Page:
  • 1