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Blu-ray Discs -- Coating Issues?  

post #1 of 121
10/3/07 at 2:26pm
Thread Starter 
http://marsbox.com/blog/news/cracked...-disc-problem/

I've seen a lot of folks complaining about cracks on Blu-ray discs from Blockbuster and Netflix. It seems like there is a problem with the coating perhaps, but whatever the cause these discs are now toast. How many have come across issues like this? What is the root cause?

Quote:
I recently started renting high definition movies on Blu-Ray and HD-DVD discs from Netflix. So far I've received 7 Blu-Ray discs from which 5 have been defective. All five of them have the exact same small crack at the edge of the disc. The crack is usually a little more than a quarter of an inch long, somewhere along the edge of the disc. Before noticing the crack, I thought I was merely having trouble playing the new discs. New technology, new headaches; I'm used to that. A friend mentioned to look closely around the edge of the disc for a small crack. The crack was so faint and small I hadn't noticed it. Problem solved I thought. A couple clicks on Netflix's well designed site and I would have my replacement disc in a mere day. No dice. The next disc was cracked as well.

I've been a paying customer for around 4 years now and I can only remember receiving one or maybe two bad discs during that time. I have phoned Netflix a couple times so far. I initially called to confirm whether other people where having this problem or if it was just me. I had receive 3 bad disc out of 4 at that point. The representative said they were unaware of anyone else having issues with the Blu-Ray discs. She offered me a discount on my next month's service, which only made me feel cheated when I saw other people getting bigger discounts for 6 months. I called again when I recevied the forth defective disc. I wanted to verbally update them that I've 4 out of 5 now, and thought perhaps a different representative might have more information than the first. The second agent also stated they were unaware of any issues with cracked Blu-Ray discs. I questioned why I received a small discount on my next month's service while I had read others had received a 6 month discounted service. To this the new rep offered me an extra movie a month for two months. I really like Netflix, so it's hard to be mean, but a couple a free movies and a small 1 month discount versus 50% off for 6 months... (sigh, nice guys lose again).

It's just a theory, but there appears there might be a problem with older discs. This could be related to the age of the disc in which all Netflix Blu-Ray discs will eventually have the problem, or perhaps just a batch of first generation discs that crack going through the mail or some sorting machine. I say this because I've seen others with the same problem but the problem seems to go away. Perhaps they rent older movies at first and then move to new releases? Perhaps the first discs they rent are some of the first Blu-Ray movies available? I'm not sure, but I'll update this post with any new information I get. So far the defective movies I've received are:

9/13/2007 - Casino Royale
9/17/2007 - Casino Royale
9/18/2007 - Flags of Our Fathers
9/18/2007 - The Holiday
9/21/2007 - The Holiday
9/27/2007 - The Holiday
9/27/2007 - Planet Earth: Complete Collection: Disc 1
10/02/2007 - Happy Feet
10/02/2007 - Babel


Mods: If this is better served in the insiders thread please move it there.

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post #2 of 121
10/3/07 at 4:07pm
Yup.... The BD disc has very different bending/tensile strenght on the top versus the bottom due to assumetrical structure (1.1mm base with 0.1mm top). To top has two different coatings (the cover and "hard coat") both of which do not like being bent as much as the softer plastic underneath. Put the disc in mail a few times and with enough bending back and forth, you have what they see here.

HD DVD and DVD have similar substrate for the two halves so don't suffer this way...

Laws of physics are pesky this way .
post #3 of 121
10/3/07 at 4:14pm
It could be temperature stress, so you may see this more often in mid-winter and mid-summer as they sit in mailboxes and mailbags.
post #4 of 121
10/3/07 at 4:14pm
Quote:
Originally Posted by amirm View Post

HD DVD and DVD have similar substrate for the two halves so don't suffer this way...

heh. which also happens to make those discs MUCH easier to scratch than Blu Rays.

Anyway, in my anecdotal experience with netflix, i've had exactly zero playback issues with HD-DVD's or Blu Ray discs. probably had about 20 of each filter through my XA2 and PS3.
post #5 of 121
10/3/07 at 4:15pm
I've had a very different experience. I've received 25 BD's from Blockbuster Online this year and only one has been damaged. It had a sharp impact in the middle of the disk like maybe a corner of something solid had struck it. Other than about 2.5 mins in the middle of the movie that I had to skip past the movie played fine.

In comparison I've received 53 DVD's this year and 3 of them were damaged.

IMO BD's are no more or less subject to damage from mailing.
post #6 of 121
10/3/07 at 4:15pm
Quote:
Originally Posted by amirm View Post

. . .due to assumetrical structure (1.1mm base with 0.1mm top).

i think you meant asymmetrical.
post #7 of 121
10/3/07 at 4:18pm
I have had no problems with the Netflix rentals here in NYC... Although I am HD DVD only, I have not even seen any of them scratched. I would assume the blu version would be just as good in terms of shipping quality control...

Maybe an isolated region?
post #8 of 121
10/3/07 at 4:18pm
Quote:
Originally Posted by elvisizer View Post

heh. which also happens to make those discs MUCH easier to scratch than Blu Rays.

I don't remember having any problems with my DVDs or CDs due to scratches.
post #9 of 121
10/3/07 at 4:21pm
Quote:
Originally Posted by elvisizer View Post

i think you meant asymmetrical.

Wow, I really butchered that one!
post #10 of 121
10/3/07 at 4:22pm
Quote:
Originally Posted by elvisizer View Post

heh. which also happens to make those discs MUCH easier to scratch than Blu Rays.

The OPU (optical pick up) can read through many scratches. Not so on a crack like this. Nor can it seek past it because the OPU cannot normally re-focus in less than a track.....
post #11 of 121
10/3/07 at 4:27pm
Never had a cracked BD from Netflix out of 40 or so.

I've had one that was scratched up and wouldn't play: "Invincible". Curiously, the replacement they sent me was also scratched, but at least it played. I wonder if that title somehow didn't get a hard coat on it? Every other BD I've received from Netflix has been pristine.
post #12 of 121
10/3/07 at 4:45pm
Been renting bluray titles from NetFlix for a while now and so far no problems for me. I think this is an isolated case usually caused by bad handling of either the customer or mail man. I guess law of physics is too much for an explanation. All i know is that you are not supposed to bend any disc regardless if it is an dvd, hd-dvd or blu-ray.
post #13 of 121
10/3/07 at 4:48pm
I have experienced one of these "cracked" edged BDs from Netflix. It happened just once (been renting 1-2 BDs a week since January) and did affect playback. I have found scratched HD DVDs to be more of problem than my single BD cracked disc experience which is why I tend to rent the BD version whenever possible. The coatings are great for rentals based on my experience.
post #14 of 121
10/3/07 at 4:53pm
I've only rented a few BD's, but the first one I got (The Descent) had a crack just like what the OP described. I was freaking out thinking there was something wrong with my PS3, and they I noticed that tiny little crack around the outer edge.

Scratches suck, but with a crack the disc won't read at all.
post #15 of 121
10/3/07 at 4:56pm
Quote:
Originally Posted by WayneL View Post

It could be temperature stress, so you may see this more often in mid-winter and mid-summer as they sit in mailboxes and mailbags.

I think any optical format can suffer on the rental market. I have had many DVDs over the years that had playback issues due to uncaring renters. Heck, any title that is "child friendly" at the local library looks like it went through a war zone. A good cleaning will usually make it playable however.

I doubt this will be an issue for most forumers here on AVS as you are probably like me and prefer to own your movies.
post #16 of 121
10/3/07 at 5:14pm
I received and viewed a number of rental BDs from Netflix and haven't had a problem. And I haven't heard of such a problem. The quote from the opening poster is very strange. He/she claims to have received nine defective Blu-ray discs from Netflix over about a 2 1/2 week period. Since anecdotal evidence suggests that such defective discs are exceeding rare the quotee is either EXTREMELY unfortunate (his odds of getting those discs must be similar to drawing back to back royal flushes) or he not telling the truth or he's damaging the discs himself. I would rule out the first possibility.
post #17 of 121
10/3/07 at 5:18pm
Quote:
Originally Posted by whippersnapper View Post

And I haven't heard of such a problem.

It's been posted on this forum quite a few times.
post #18 of 121
10/3/07 at 5:19pm
I believe it is possible for the post office sorting/stamping machine to be the root cause.

Assuming that the BDs are more rigid, they may not go through the machines as easily.

Interestingly enough I know of one person who has had trouble with BD from Netflix but not from Blockbuster. Apparently Blockbuster uses a better mailing package.

That info is second hand though, no personal experience with this issues.
post #19 of 121
10/3/07 at 5:22pm
Why do people scratch discs? How hard is it to keep discs in good condition? I mean all you have to do is put it in the tray and let it play; no hardwork needed!
I rent DVDs once in a while and wonder what people have done to discs! Personally I keep my discs as pristine as possible.
post #20 of 121
10/3/07 at 5:32pm
Quote:
Originally Posted by amirm View Post

Yup.... The BD disc has very different bending/tensile strenght on the top versus the bottom due to assumetrical structure (1.1mm base with 0.1mm top). To top has two different coatings (the cover and "hard coat") both of which do not like being bent as much as the softer plastic underneath. Put the disc in mail a few times and with enough bending back and forth, you have what they see here.

HD DVD and DVD have similar substrate for the two halves so don't suffer this way...

Laws of physics are pesky this way .

Do they weld BDs to the box hub the way they do some SD DVDs? Just freeing it for the initial play could problematic.
post #21 of 121
10/3/07 at 5:43pm
Quote:
Originally Posted by wakashizuma View Post

Why do people scratch discs? How hard is it to keep discs in good condition? I mean all you have to do is put it in the tray and let it play; no hardwork needed!
I rent DVDs once in a while and wonder what people have done to discs! Personally I keep my discs as pristine as possible.

A crack worries me more than a scratch, scratches you make, but cracks can be a structural issue if in a coating or varnish. Scratches can be fixed, not cracks.

I'll be honest, and I've been honest about this since day one, I hate the idea of hardcoat, I've never had any luck with protective coatings on slick, non-porous surfaces. I've had it on glasses, windshields, archival framing glass, and there is alway a problem with either separation or breakdown as time goes by.

Maybe not this time, but in my mind only the passage of time will tell.
post #22 of 121
10/3/07 at 6:44pm
i have never had any problems, and i think this is WAY over blown. I have had a few problems with DVDs, but even there it was like 1 out of a hundred.

so why this post op?
post #23 of 121
10/3/07 at 6:46pm
Quote:
Originally Posted by lomax View Post

so why this post op?

I wonder
post #24 of 121
10/3/07 at 6:47pm
Fud
post #25 of 121
10/3/07 at 6:50pm
All the BD's & HD-DVD's I've received from Netflix have worked fine. No issues here in South Carolina..
post #26 of 121
10/3/07 at 7:06pm
Quote:
Originally Posted by amirm View Post

Yup.... The BD disc has very different bending/tensile strenght on the top versus the bottom due to assumetrical structure (1.1mm base with 0.1mm top). To top has two different coatings (the cover and "hard coat") both of which do not like being bent as much as the softer plastic underneath. Put the disc in mail a few times and with enough bending back and forth, you have what they see here.

HD DVD and DVD have similar substrate for the two halves so don't suffer this way...

Laws of physics are pesky this way .

I don't know if the tensile discrepancies are much of an issue; last week in a fit of rage my girlfriend grabbed one of my BD's and tried to break it in half - we're talking bending here to an angle of greater than 60 degrees in acuteness from the default 180 flat plane. That to me seems far more extreme than what one would expect discs to experience in the mail bag. But to my amazement, not only did the disc survive, it experienced no playback issues.

Netflix problems stem either from the automated post office handling - an issue of impact or point tension in this case - or from the theorized issues with DVD-style procedural resurfacing of discs that aren't meant to be resurfaced. But whatever the case, I can say with great confidence that these discs can stand up to extreme levels of tensile duress.

PS - Aren't these the sorts of threads that should be in the BD forum? It seems whenever there's a positive BD-specific thread, it's immediately locked, moved, or deleted from here. But whenever there's a negative BD-specific thread, it is allowed to live on indefinitely in HD software.
post #27 of 121
10/3/07 at 7:17pm
Quote:
Originally Posted by xbdestroya View Post

I don't know if the tensile discrepancies are much of an issue; last week in a fit of rage my girlfriend grabbed one of my BD's and tried to break it in half - we're talking bending here of greater than 60 degrees in acuteness from the default 180 flat plane. That to me seems far more extreme than what one would expect discs to experience in the mail bag. But to my amazement, not only did the disc survive, it experienced no playback issues.

Did you run at her with calipers out to measure the angle as she was bending it? Get her back to bend it the other way.

It's not the extremes I worry about, it's time and average wear.
post #28 of 121
10/3/07 at 7:21pm
Quote:
Originally Posted by Timothy Ramzyk View Post

Did you run at her with calipers out to measure the angle as she was bending it?

Well, she bent it until her hands were touching, if that's an indicator. By her own account she claims that previously CDs and DVDs have fallen victim to equivalent attacks on her part; I guess some grim consolation there (or something!)

Quote:


It's not the extremes I worry about, it's time and average wear.

I would say this to that: I have not heard of private owners experiencing these issues, and to the contrary most any BD owner will sing the praises of the hardcoat. I know I certainly count myself among those. For now, I would definitely tally up damage through Netflix to situations completely anomalous to what the average BD will experience in its lifetime.
post #29 of 121
10/3/07 at 7:45pm
I have never seen one of these cracks in person, but I have seen them in pictures... and they sure don't look like cracks due flexing the disks. I would say they look more like stress cracks brought on by some kind of shearing force.... and i would GUESS heat. Two dissimilar objects with dissimilar expansion qualities will expand at different rates... and because they are stuck together... something has got to give. A bi-metal spring inside a thermostat works this way... 2 dissimilar pieces of metal glued together will cause a warping action of the spring when heated. Not withstanding, the data side always receives more heat which quite naturally in itself will cause uneven heating.

The most common player on the market right now is the PS3.... and we all know how hot they can get.

Just speculative theory... nothing more
post #30 of 121
10/3/07 at 7:48pm
Quote:
Originally Posted by bigbarney View Post

I have never seen one of these cracks in person, but I have seen them in pictures... and they sure don't look like cracks due flexing the disks. I would say they look more like stress cracks brought on by some kind of shearing force.... and i would GUESS heat. Two dissimilar objects with dissimilar expansion qualities will expand at different rates... and because they are stuck together... something has got to give. Not withstanding, the data side always receives more heat which quite naturally in itself will cause uneven heating.

The most common player on the market right now is the PS3.... and we all know how hot they can get.

Just speculative theory... nothing more

Your theory is based in science, but you're ignoring the clear anecdotal evidence that:

a) the vast majority of BD owners on this forum own the PS3

and

b) none of us have had cracks develop due to PS3 playback...

I think that should have put you on a different path straight away. Shearing forces - exactly. Which is why the majority of us think these problems stem from either the post office auto-handlers or Netflix resurfacing (BDs are not to be resurfaced).

I find it a little comical also that the majority of "theories" on this issue are coming from HD DVD owners that have little to no experience either with the discs themselves or in discussing where these issues may be stemming from over the last several months. This isn't a new phenomenon guys, and it's not anything the private owner is having happen to their own collections either.
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