[unfamiliar]

My main use case is family/holiday videos. Saving massive pro-res files would fill up the space quickly and I’m not sure how to process them into HEVC quickly and simply.

[jpc0]

Higher bitrate HEVC won't be any smaller than the same bitrate ProRes.

Why would you think that it would be?

[turnsout]

You must not have tried ProRes on the iPhone. ProRes HQ consumes around 1.7GB per minute, which is an order of magnitude more than the HEVC bitrates.

Apple: "ProRes files are up to 30 times larger than HEVC files." [1]

[1]: https://support.apple.com/en-us/HT212832

[dylan604]

I don't even have a clue how to force HEVC to use the same bitrate a ProRes file would use. HEVC is very efficient, and does not always use the full amount of bitrate being allowed. That's its the entire point for being. Trying to get "high bitrate" HEVC is one of those "you're holding it wrong" moments.