www.makemkv.com

I noticed with some of my very early 4k bluray rips I'd not encoded them with the Dolbyvision / HDR metadata passthrough correctly in handbrake, so I decided to re-rip and re-encode them correctly. Most worked fine except for 2.

Star Trek 4 The Voyage Home
Start Trek 10 Nemesis

I submitted the dumps as per the FAQ, but the question is, I've used these same physical discs and the same drive and makemkv to rip these discs when I bought them, why are they unknown now (yes the makemkv version is a little later, but that's it)

Checked the error log, it's not a blockage getting the decrypt data, it just thinks these cannot be decrypted, yet my earlier rips and encodes prove they are.

Just curious to how and why this could happen ?

If you were able to rip them before but can't now, it's possible that the key has been changed or removed by MakeMKV in recent updates. Check if there's a new update and update it.

DessieJerde wrote: ↑

Mon Mar 24, 2025 1:28 am

If you were able to rip them before but can't now, it's possible that the key has been changed or removed by MakeMKV in recent updates. Check if there's a new update and update it.

VERY unlikely, compared to the possibility of disk contamination. MakeMKV keeps its keys separate from the program, and that list keeps growing.

It's more likely that the disk, when stored in its housing, has picked up a "film" of contamination. Quite often, you can see that contamination by wiping a clean cloth across the case. Doing so with a proper microfiber cloth across the disk itself (always moving across the diameter of the disk, not circularly) can make it apparent, too. I clean disks that have been in their cases more than 6 months before I rip them. Sometimes, it's necessary when they're new, but usually it takes a few months to transfer.

that's really interesting, it must be ~6 months from when I last used the media, I'll give them a proper clean and see if it makes a difference, I'd not considered anything along those lines, thank you

big surprise, it worked, the discs looked clean, I'd given then a wipe, gave them a proper clean as you suggested, they both worked.

Great suggestion.