Pressed vs burned DVD longevity

vbimport

#1

I have some precious home movies which I have backed up as identical MPEG files on a pair of eternal hard drives.

But I would like to also copy them to DVD. Then I recalled a claim someone made that movies issued on commercial DVDs have longer life spans because DVD studios “press” the DVDs rather than use computer DVD 'burner" drives.

Is this true? If so, than assuming one uses reasonably reliable (Verbatim? Sony?) blank dual-layered DL +/- blank media and burns the disk at a slow (more error free?) speed, what DVD lifespan could one expect, compared to a pressed copy?


#2

It is true that commercial dvds use a pressed layer rather than a dye layer like those used in burnable disks.

DL dvds have a rather complex internal structure and may not be the best choice as an archival medium. Verbatim +R DL disks are the best available if you must use double layer media.

Burning at extremely slow speeds is not recommended either. Neither the firmwares in modern drives, nor the media we have available these days is optimized for best results burning at slow speeds. As a general rule of thumb the slowest speed you should use is 8x when using 16x single layer dvds.

As to longevity, no one has a definitive answer for you. There have been some studies done using stress tests on burned media, but the results and longevity predictions vary quite a lot depending on which group you listen to. Estimates vary from 30yrs to 100yrs in ideal storage conditions.

If you want to look through a paper describing dvd structure, and the care and storage of dvds look at this file: http://www.itl.nist.gov/iad/894.05/papers/CDandDVDCareandHandlingGuide.pdf

Just a FYI, this is a pdf file and make take quite a while to load, depending on the speed of your internet connection.


#3

Thanks so much for this VERY valuable info. I just assumed that since I read that reading audio CDs at lower speeds while ripping select tracks may
generate less errors, that the same applied when burning audio/video data to DVDs. And thanks for the heads up about the potential problems with
DL discs as opposed to SL ones.


#4

Audio CD and video DVD are completely different supports, and completely different are also data stored in them, so it is a nonsense to do a comparison :slight_smile:

Bear in mind that there are also a lot of myths about audio CD ripping, and most of them are totally false :doh:

My suggestion for backup is to keep the originals in a safe place untouched, and for everyday usage make a copy on DVD (single or double layer as you prefer) or on external HDDs as you already do. When the copy is not more usable, you can make another from the original.

If you are concerned that also the pressed disc can become damaged in some way, you can also make a backup of the original disc with a trick to improve safety. I suggest to rip the original disc as ISO file on HDD, then make a RAR archive of that ISO file splitting it into 1GB chunks. Very important: when creating the archive, be sure to add parity data on archive (I like a lot WinRAR for this feature). Then store these chuncks on a couple of DVDs or on HDD.

If you need to restore original data, is it sufficient to extract the ISO file from archive :slight_smile: