Strange DVD compatibility issue – check disk will play on DVD players, but NOT on DVD players (different result for check disks from DVD author and replicator)

[Khashyar Darvich]

Thanks for your feedback and advice, Eric.

Yes, thank God this is a rare issue (thank God for all of us, except for me in this instance :). ).

Thanks for referring me to that website. I’ll look at it once I get back to my computer.

Khashyar

[Dave Friend]

Khashyar,

I wanted to know if the Mac mounted the disc because I have read of a situation (very rare and not related to Scenarist) where disc permissions get interpreted by OSx such that the disc is not allowed to mount. That’s not your problem.

I will ask the guy who runs our glass mastering laser if he has any ideas what could be going on.

At the start of this thread you said, “The Replicator’s glass master “Stamper” reports back is a DLT fails for some reason, but they were able to play the DLTs on their system.” This is troubling. If they had trouble reading the DLT then I would be nervous that the data on the disc is corrupt. Sometimes the DVD player “dirty disc’ code you are seeing is due to corrupt data.

[Khashyar Darvich] “My last step would be to ask our DVD Author to output NEW DLTs”
With Scenarist it is possible to output what Sonic calls a PlantDirect image. This “image” is the set of files that get written to a DLT saved to a hard drive. Check with your replicator but most likely they can use these files by reading them from a DVD-R. This is much faster and cheaper than writing DLT tapes.

Dave

[Dave Friend]

[Khashyar Darvich] “Could this be an issue of recalibrating the Replicator press, even though our check disks do work on stand-alone DVD players, just not on computers?”

Not likely. I would expect a replicated disc that not quite up to spec to have problems on a wide spectrum of players – both computer and stand-alone.

You have checked the sample disc on several stand-alone players? Run it through as many machines as you can find just to be sure.

Dave

[Khashyar Darvich]

Hi Dave,

Thanks for your response.

The Replicator’s check disks played on 26 different standard DVD players at their test facility, and 4 other stand-alone DVD players that we have.

So, they are playing solidly on stand-alone DVD players, but only on about half of the computers that we tried.

And, again, the DVD Author’s check disk (which should be the same as the Replicators, except without CSS), does play on our computers.

Khashyar

[Khashyar Darvich]

Hi Dave,

Thank you again for contributing your thoughts in trying to find the solution to this issue.

And thank you very much for asking the opinion of the person who creates your glass masters.

In the sentence that you mentioned from my first post, I miswrote “is.” That word should be “if.” If there was a problem with the DLTs, then the Stamper would have reported a DLT tape fail, but our DLTs passed and did not fail, and they were successfully able to create a glass master.

I am wondering that since the DLTs did pass, and a glass master was able to be successfully created, could there still be correuption on the DLTs?

I am not sure if the glass master stamper can accept a hard drive “direct” output, but I will ask them.

Thanks again,

Khashyar

[Dave Friend]

[Khashyar Darvich] “I am wondering that since the DLTs did pass, and a glass master was able to be successfully created, could there still be correuption on the DLTs?”

Yes, it is possible. Not likely, but possible.

I talked with our mastering guy and he offered to run your check disc through our checking system to see if anything jumps out as wrong. I will send you an email via the contact us link on your website to give you my contact info.

Dave

[Dave Friend]

[Khashyar Darvich] “So, they are playing solidly on stand-alone DVD players, but only on about half of the computers that we tried.”

All the same O/S make and release version? Maybe you found a bug in that version of that O/S.

Stand-alone players tend to be a bit more tolerant as they have built-in error correction. Drives in computers are only emulating a stand-alone and rely on software for much of what is “in the chips” of set-top players.

As the data can be figured out by one type of player and not another would seem to indicate a physical problem with the disc IMO. If it were strictly a “bad input” issue (i.e. corrupt DLT, out-of-spec build, bad authoring) then wouldn’t all players behave the same?

It’s also important to bear in mind that the replicator will have to mount the stamper (The stamper is made from the “glass master”) in the press again. So if the problem is a physical one due to the molding process it might not manifest again on the next replication run. Then again, it might get worse.

The replicator should be able to tell you if the data on the disc is exactly the same data that was used by the mastering laser. Perhaps they don’t do that on “check” runs? They should on a “real” run.

You have no reason to believe that it is an authoring issue. Frankly, I believe the replicator needs to either make another run or pony-up for third party verification.

If the disc passes a physical QC review I would offer to provide the DDP data on DVD-R. As I explained earlier, this is done by using the PlantDirect feature of Scenarist. The DDP file-set for each layer (as created by Scenarist, there are four files in the set) are burned to individual DVD-R discs. If your replicator can’t handle that then go elsewhere for the work.

Really it comes down to the fact that the replication check discs are not satisfactory. My offer to run the check disc through our QC suite (at no charge) stands.

Dave