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Comment by mrfinn | Hacker News Reader

> BD-R (dye or non-dye, single layer or dual layer) 5 to 10 years

> BD-R (non-dye, gold metal layer) 10 to 20 years

> BD-RE (erasable Blu-ray) 20 to 50 years

I find hard to believe that info. Seems to be sustained by a single study. That would mean that bluray (specially the BR-R format) is a pretty flawed technology.

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I haven’t seen a BD-R in my entire life. In fact, the only use of BR I’ve had is on the PlayStation. The technology came way too late.

My educated guess would be something along these two threads:

* Higher data density => tighter tolerance => same physical degradation is more catastrophic (DVD ~7x density of CD, BD-R ~20/10/5x DVD density = up to 140x CD density)

* Produced later and therefore like all consumer goods, less regard for durability and more regard for absolute cost optimization

That means first games for PS4 are already damaged.

I’m under the impression that ps4 discs are pressed. This article is about writable media.

Writable media needs a dye or layer that can be ‘burnt’

Commercial disks don’t do this and instead are physically pressed.

The dye material is the one that degrades over time. The pressed material doesn’t.

Someone correct me if I’m wrong?

Commercially pressed discs should last a very long time in comparison

Basically correct, with a tiny caveat: there can be manufacturing defects where the reflective aluminum layer of pressed discs is not fully sealed and oxidizes over time.

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