such thing as disc data disappearing? how long do DVDs last?

slacker · Member Joined: 05 Jan 2004 Location: SF, CA, USA

When all the rhetoric has disappeared, all of us are left with ONLY empirical evidence, i.e. what actually worked and what didn't. That is what I ultimately use to judge anyone's or anything's performance in this world. On this site alone, I hear about more dvd read/write failures in one week that I've experienced in all 25+ years of using tapes in corporate and home environments.

Tape worked, continues to work, and SHOULD continue to work into the future. It has proven itself! That still CANNOT be said of these cute plastic discs. In real life, these discs along with the writers and readers they rely on fail over and over and over again. Period. They are fun for passing around video, music, and such to friends and family in the short term. But for archiving? They receive a fail grade. No thanks kiddo.

Buzzword · Member Joined: 09 Oct 2004 Location: Sacramento, CA

Just so I clarify the intent of my original post, I was interested in finding out if there is further evidence to support the statement that dvd-r's only last about 7 years. That, to me, is a radical departure from all other claims of longevity I've heard these past few years. For those of us who make money doing media conversions I won't complain...it will help me to continue to earn $$$ from those who don't want to mess with the process.

The tape vs. dvd archiving argument really is a separate issue compared to the advantages of storing one's personal videos on a dvd: chapter points, menus, etc. It would just be nice to know if in 6+ years - rather than 25 - consumers will have to start worrying about replacing their deteriorating disks.

Stay tuned, I'll report back here in 2013.

slacker · Member Joined: 05 Jan 2004 Location: SF, CA, USA

The problem is...

The guy off the street doesn't know all this stuff, doesn't have a clue. To convert someone's cherished video from VHS or Hi-8 or whatever to dvd without letting them know about the limits of the physical media, as well as the existence of possible alternatives, borders on the unethical. As long as your customer is informed...

impmon2 · Member Joined: 31 Jan 2002 Location: United States

Just to add my info on discs: I've burned the entire japanese series across 15 DVD-R (ritek 5) and they all played perfectly the first time. They played fine a few times over the span of 6 months until a couple days ago. Discs 7 and 8 were skipping a lot, lagged in video and images were breaking up a lot. This happened regardless of which player (2 portable DVD players, 2 stand alone players, and a PC running PowerDVD). The PC software even hung up and I had to force a restart.

A through check revealed a lot of read errors across that 2 discs. There are NO visible scratch, dust, smudge, etc. So I guess these 2 discs just failed after just a few plays over 6 months. Thankfully I had original on my PC so I just reburned fresh copy. Will post back if I run into more problem with the rest of the 6 months old set.

faithfoo · Member Joined: 01 Jul 2003

lord smurf seems to be saying that DVDR ( dyed ) are more
longer lasting than DVD RAM ..... i do not see anywhere that he says that DVD RAM Is most reliable or Large corporations and businesses backup data on RAM for it's reliability ?

Joe Ryan · Member Joined: 03 Dec 2003

Dye-based media (CD-R, DVD+/-R) use different dyes that are susceptible to damage from UV light, heat, and humidity. Some dyes can break down in as little as 3 months (CD-Rs that were not cured before the sputtering vacuum chamber in order to save costs.) A good quality CD-R using phthalocyanine dye (most of them) should last about 70 years if it was recorded well and kept in good storage conditions. DVD+/-R use a less stable cyanine or azo-cyanine dye as well as a sandwich construction. They are more susceptible to humidity than CD-Rs and are less tolerant of changes in flatness. The best they can expect is about 35 years under the same conditions. These estimates are based on environmental testing according to the Eyring formula and using two stress levels of heat and humidity.

Phase change media are not affected by light, only heat and humidity. If the targets used for the evaporated metal are correctly chosen and have no contaminants, the discs may last even longer than dye-based equivalents. Certainly DVD-RAM, with its dielectric thermal layers, is the longest lasting of the common phase change discs. The problem with phase change materials is that the quenching/recrystalization process depends on the uniformity of the shape of the recording laser. If that varies because different drives are used, then problems arise. The greatest problem, however, is incompatible formatting. That causes more losses of people's data than any other factor in CD-RW problems.