Defective DVDs? Anybody know about the manufacturing Process?

From my experiance I'd have to say don't worry about it-I base this on my collection of over 3000 dvds-some 10 years old.

Ahhh...but the interesting question would be "how do you know?" With some 3000 DVDs there must be a high percentage of ones you haven't watched in quite a while. There is no way of knowing without playing them to tell if any have gone bad.

Ya wanna bet?

How are you going to prove it?

With that many disks, if you watched one a day every day it would take over eight years to watch each one. Within the eight years between viewings any numbers of them could have suffered from DVD rot without you knowing it. While there may be visual indicators in some scenarios (e.g., "Have Gun Will Travel" disks changing color from oils in the cases), I don't know that this is always the case so it may take watching to verifiy one way or another.

To the op: Whether it be bad pressings in general or DVD rot you don't hear enough about it to be alarmed, but I would think most purchase with the idea they will last along time, if not a lifetime of viewing. While there is no technical reason that I know of that would limit their playability, who can say for sure until they are played 20, 30, 40 years later.

I don't think you can compare blank DVD's that you buy for burning to manufactured disks of movies. They are manufactured differently for two different purposes. For blank disks, ther are produced so that an image can be burned into it after production. They are more susceptible to going bad or being damaged. While the movies you buy are pressed into the disk during the manufacturing process. At least this is my brief understanding.

Here is link to further your education about commercial vs recordable media. Enjoy.

http://adterrasperaspera.com/blog/20...archival-media

The point I was trying to make by giving you the link is to show that commercial DVD's are made by pressing pits into an aluminum substrate and then sealing it. The DVD media isn't bought but manufactured when the DVD is created. The media we buy(DVD-R, +R, +RW) to record at home use a dye, not an aluminum substrate. It won't have the same appearance as a commercial DVD and isn't sold to distributors of commercial DVD's.
The other point is that commercial DVD's fail when air gets into the aluminum layer and causes oxidation of the pits. Home media can fail for a lot of reason, bad burn, defective DVD, cheap dye

You are returning DVDs because you don't like the way the disks look, even if they play ok??

You still haven't made it clear if you are talking about store-bought movies or recordable media. That makes any discussion sort of difficult.

All DVDs are made with 2 polycarbonate discs (stampers). Between those 2 discs is either a layer of foil (store-bought movie) or a layer of organic dye over a reflective layer, (recordable). In either case, whatever is applied to the back side in the way of a coating has no impact on the integrity of the disc. Unlike CDs, which are made of a single disc with the reflective layer applied on the back, which is somewhat vulnerable.

IF you're talking about recordable media, then yes the factories do make different "grades" of media. Or rather media is graded after it's made. And OEM media that's made to spec may not be the same for one brand as it is for another, even though it comes from the same factory and even uses similar materials. For example, Office Depot buys factory seconds and puts it's own brand on them. Maxell may buy from the same maker, but orders the media to spec. Memorex may also buy from the same maker, but takes the A-stock and adds it's brand. All are the same materials from the same factory but can be very different quality, or all the same quality depending on the quality of that particular run.

Coatings are generally applied by spinning the disc and dropping a liquid onto it, keeping it spinning till it's dry.

IF you're talking about plain silver-back recordable media, (generic), then the silver that you are seeing is the reflective layer inside the plastic sandwich. DVDs are extremely durable on the backside, you really cannot hurt them.

OK, well in short if you're looking at the "data side" of the DVD, any irregularities are significant. If you're looking at the back side, they are not.

I keep pretty close tabs on my collection and belive me-I'd know if one went bad.

So maybe I got it wrong. Maybe you watch 8 movies a day thereby allowing you to watch all 3000 DVDs in one year because I don't think anyone can know for sure if one went bad other then to play it.