4K UHD disc protective coating

[cupboy]

So does this coating prevent scratches or do 4K UHD discs get scratched anyway? The reason I'm asking is I have an opened case with a loose disc inside. Once I open it should I expect scratches on the disc and something that is unplayable? I already know 4K UHD discs are sensitive enough that even a spec of dust can cause a freeze-up.

[Vilya]

The coating is scratch resistant, but the discs can still get scratched.

[rdodolak]

UHD Blu-ray discs use the same scratch resistant coating as Blu-ray discs. The disc should be fine.

[FilmFreakosaurus]

Originally Posted by rdodolak

UHD Blu-ray discs use the same scratch resistant coating as Blu-ray discs. The disc should be fine.

Actually, it seems like the coating is weaker/less robust on 4k discs than normal Blu-ray discs. I've come across a lot more scratch issues with 4k discs, especially if they're stacked.

[Vilya]

The coating is the same, but 4K discs are far more sensitive to surface imperfections.

[FilmFreakosaurus]

Originally Posted by Vilya

The coating is the same, but 4K discs are far more sensitive to surface imperfections.

It's not the same because it doesn't take as much effort to scratch the 4k discs' surface. They probably skimped to try and make them cheaper to manufacture than they would have been.

[Vilya]

The protective coating is indeed the same. It isn't that it is easier to scratch a 4K disc; it is rather that any such scratch is more likely to cause errors. The data density on 4K discs is higher than that of a blu-ray disc and higher data density makes any surface imperfection more problematic as it adversely affects the reading of a larger portion of data. A scratch that would not cause a blu-ray to falter may very well cause a 4K disc to malfunction.

The blu-ray disc association offers a number of brain numbing white papers:

http://www.blu-raydisc.com/en/Techni...ers/BDROM.aspx

See the 3rd link, read sections 3, 5, 6, and 13 of this white paper if you can stomach doing so.