Blu Ray discs with bronze/gold color bottom?

[PantsHalo]

I've been going through and selling off a lot of my old DVDs and some blu rays. I've learned to spot disc rot via staining and bronzing and the like.


However, I've found that a whole lot of blu rays I have, ranging from between 2-10 years old, are somewhat bronze or gold colored on the bottom. They don't have any signs of wear or deterioration or staining, the color is all pretty much solid and flat.


Is this disc rot? Or is this color natural for certain blu ray discs? There's no real consistency in terms of which discs are bronze colored, ranging from Sony to Universal to Warner Brothers to Arrow. Should I be worried nonetheless?


EDIT: I might be dumb as hell as I realize a lot of this might not actually be the bronze color but just the purple-ishness of blu rays reflecting off the lighting to make the disc color seem slightly bronze in tone (the light in my room is very warm)

[HorrorBlu]

In my experience, the ones with playback issues will have notable inconsistencies on the playing surface. For example, the notorious LionsGate rotters will typically have white / purple dots appearing all over the playing surface. Other times, you'll see a discoloration creeping in from the edges of the disc (typically a bubble under the surface).

Not to state the obvious, but why not stick it in the player and skim through the chapters?

[PantsHalo]

That's been my experience too (the "coffee stain" like discolorations and the like) but I've been skimming DVDs and some blu rays and not finding much errors or issues at all.


The only serious issue I've had thus far has been with 3 dvds, one of which had the discoloration around the edges, the other had it starting from the center and creeping outward, so the edges of the disc were still silver but the center was deep bronze. There wasn't a sharp delineation between the colors, it just gradually faded between the two


None of these blu rays though have any sort of discoloration. They're just all one singular color. Some are more bronze than others, but I'm starting to suspect it's just a case of the lighting in my room.


When I take them to a different light source, most of them aren't bronze anymore, but pale purple. The more deeper bronze ones are lighter bronze. Am I tricking myself due to the lighting?


EDIT: These are DVDs, not blu rays, but this is sort of what I'm talking about

https://imgur.com/a/6nR3jSM

These are three discs from the same set. One is noticeably darker than the other two. There's no other problems like wear or scratches or stains. Should I be worried?

[Eidolon]

bronze/gold was the standard colour for dual layer discs for the first few years of DVD, it's completely normal for DVD. I'm not sure why they eventually changed the colour, or even the reasons for them being gold in the first place. Maybe something to do with manufacturing techniques of the time.
It shouldn't be anything to worry about. Bronzing in Blu-Rays is another thing altogether, and a very real problem. I've had a Hong KOng BD that did that, and it became completely unplayable. Only watched once too. If a BD is going bronze, then it's almost certainly dying. I have one at the moment that has an odd discoloration that I've not seen on anything else. It's a little towards the purple end of the spectrum around the inner half of the disc, and there's a soft lighter line between it and the outer part of the disc, whch is normal coloured. Still plays fine. I'm not sure if it's inherent from the manufacturing and nothing to worry about, or if it's something that's spreading outwards.

If something is noticeably discoloring, as in changing colors from what it used to be, then theres a problem, BD or DVD. DIsc discolouration can take different forms, it's not limited to one particular look. I had a DVD box set in which 5 of the 6 discs literally went black.

[PantsHalo]

None of the blu rays I've looked through so far have any discoloration, and the bronze tone for most of them I think is just the warm light reflecting on their purple surfaces. The ones that are a little more deeply bronze I've been testing on my comp and so far none has had problems. Should I still be concerned about these "light" bronze discs or possibly wait on them for a few more years to see if they change?


EDIT: I've looked through a bunch of blu rays now under a white light, and most of them reflect back with a bronze/gold color. In shadow, their natural tone is more purple-ish. The ones that aren't bronze/gold tend to have a more blue-ish tone in shadow. Is this normal?