CMC media information is true or false?

[gamemaniaco]

This information (40 years) is true or untrue? CMC Magnetics said the following information about my DVD + R 16x Philips manufactured by it:

Quote:

With respect to safety of data / Iifetime of the product, CMC can give the following statement for its 16X DVD-R products:
Accelerated aging tests that follow the standard of ECMA-379/ISO-10995 allow to expect that CMC 16X DVD-R can be archived for at least 40 years if the following conditions are met:
· The 16X DVD-R are stored under normal archiving conditions (25°C , 50% relative humidity, protected against light and against dust and other pollution).
· The 16X DVD-R are treated properly, and especially the surface is not damaged by scratches, stains, etc.
· The used hardware and software for the writing and reading of the 16X DVD-R is in well condition.
· The 16X DVD-R have only been used for the intended purpose of recording data.

[lordsmurf]

The issue with CMC isn't longevity -- it's the disc having immediate issues.
When you don't test media, you can't make statements about longevity (ie, data "disappearing", etc)

A good CMC disc, when you find one, probably does last 40 years, with proper RH%, temps, lack of scratches, and in a good reader.

[gamemaniaco]

I burned the files on my DVD + R 16x Philips manufactured by CMC and tested this DVD disc with Nero DiscSpeed and was result test green 100% Good, with that tested it is possible statement or not this dvd disk keep files for 40 years stored 25 ° C, 50% relative humidity, protected against light and against dust and other pollution?

[lordsmurf]

Can/should != will
Nothing can be guaranteed.

[gamemaniaco]

It is true or false to assert cmc: 40 years if The Following conditions are met:
· The 16X DVD-R archiving are stored under standard conditions (25 ° C, 50% relative humidity, protected against light and against dust and other pollution)?

[dpalomaki]

If the initial burn was good (you can test that), then under the specified storage conditions most of the discs (probably more than 97%) will be readable 40 years later. The problem is identifying the 3% that will not. If you make two good copies. the odds improve to 99.9% (e.g., 1 in 1000 may be unreadable).

However, eliminate the possibility of getting a bad batch of discs that could fail prematurely due to conditions such as weak glued joints.)

Life is full of risks (e.g., flood, fire, revolution, component failure, earth quake, theft, etc.) and all data is at risk; you minimize data loss risk by methods such as testing, off-site backups, using quality media and equipment.

[gamemaniaco]

3% bad batch is identifiable when doing the test DiscSpeed nero? if the test is 100% good or bad?

in conditions 30-36 ° C and RH 35 ~ 64% without rain which would be the expectation of this disc? the disc was made in 2010 and I bought it in 2014

[lordsmurf]

Quote:

Originally Posted by dpalomaki

However, eliminate the possibility of getting a bad batch of discs

... and realizing that a "batch" is 10,000 to 100,000 discs, not just a spindle.

Lot of bad myths about "batches" out there.

[dpalomaki]

You keep asking the same question, although phrased slightly differently each time.

Given the information you have provided, no one here can say with any degree certainty what will happen with your existing discs, not even CMC.

If the old recordings test good today, that does not mean they will still be OK in 5, 10, 20, or 40 years.
About all we can say with reasonable certainty is that if a disc tests bad today (for reasons other than a drive or temporary surface dirt) it will not be any better in the future.

Make back-ups of the important stuff now and store them properly. The amount of time you have spent re-asking the question would have been better spent making the back-ups and ensuring proper storage conditions as described in the initial threads and posts.

[gamemaniaco]

I'll have to do several tests with nero DiscSpeed every year to see if the files are still intact?

[dpalomaki]

The number you have to test depends on the degree of certainty you want, and the number of discs of each type that you have. A course in statistics will give you the information you need to decide how many to test.

[gamemaniaco]

I said, I tested the drive with nero disc speed when burned and it was good, I test disc with DiscSpeed after two years the disc may be bad

I burned the DVD discs in 2013 and they were made in 2010 with Nero DiscSpeed I tested again my DVD + R 16x Philips (cd slim box) manufactured by CMC and the two discs presented as a result 100% Good Green

also tested two Smartbuy CDs (paper bag) that were stored in the same place of dvds and cds both had faults and read errors

because of this difference in the results? these my dvds are reliable for long-term storage? the cmc says 40 years in 25 ° C 50% RH without light (put the discs in box) the cmc lie or truth?

[dpalomaki]

We have said it before: your temperature exceeds 25 C, your RH exceeds 50% and furthermore, they vary over time; therefore, the CMC statement DOES NOT APPLY to your situation.

It is not a lie in and of itself. Trying to make it fit your case would be a lie.

[gamemaniaco]

1 I only asked if the philips dvd cmc stored at 25 Cº 50RH lightless resists 40 and keep the data, the CMC said it is true or false?

2 in my condition temperature 30 C ° ~ 36 ° C Humidity 35% ~ 64% what would be the useful life expectancy for my philips dvd?

[dpalomaki]

Ask Phillips.

[gamemaniaco]

I could not answer those two questions?

Because Smartbuy CDs had errors in the test and the Philips DVD not? DVD is tougher than cd? philips is better than smartbuy? All optical discs are stored in the same location

1 In 2016 I tested with Nero DiscSpeed 2 dvds + r philips 16x (cmc mag m01 00), the discs were burned in 2013 and made in 2010, the test results were 100% Good Green in 2013 and 2016 year, it is possible to say that these stored discs 25 Cº 50% RH will last 40 years as CMC reported?



2 What I do not understand is that I also tested two CDS Smartbuy Prodisc burned in 2013, the year I burned those discs the test disc nero speed the result was 100% good and now in 2016 the test is 98% with some errors because it is different from philips test? all cds and dvds discs are stored in the same location

[dpalomaki]

Test results are only good for when the test was made. A 100% test today says nothing about the results of a test 10 years form now. A 98% test today meany it is very unlikely you will get a higher test in the future (unless the problem was with the drive used to do the test).

Different media will age/deteriorate at different rates and the rate will depend on the environment, the chemistry of the media, the quality of the media, and the physical stresses to which the media is subject. And some media and burners are much better than others - there are other forums and posts that address that. There is no way anyone here can predict what the results with your burns will be in 10, 20, 40 years with any degree of certainty.

Time to stop asking the same questions in hope of getting a different answer.
- If having a good copy is important to you, test your burned media periodically
- Be sure to have back-up copies in a secure location.
- Track changes in test results to individual pieces of media.
- When you start to see recoverable error rates rise, consider making a new/replacement copy before the errors become uncorrectable.

[gamemaniaco]

I think I store my important files in flash drives usb looks more tough and durable than CD and DVD that are unstable

[dpalomaki]

See the past threads on solid state media (e.g., SD, CF, and thumb drives) types. While exposure to normal amounts of light is not an issue, it has other issues and unknowns. If the media type were fool-proof storge, SanDisk wouldn't be bundling RescuePRO recovery software with its media.

But read the tests, and make you own decisions as to how you manage your stored data. Using multiple types to provide duplicated back-up copies, including off site copies if important, gives the most protection.

If data is really valuable, store copies in a bank safe deposit box. That location may even be air conditioned to mange both temperature and humidity (check with the bank), and the inside of the box would be dark.

[lordsmurf]

Quote:

Originally Posted by gamemaniaco

I think I store my important files in flash drives usb looks more tough and durable than CD and DVD that are unstable

Answered this here: http://www.digitalfaq.com/forum/medi...html#post44430
Never use flash/SSD for archiving.

Quote:

Originally Posted by dpalomaki

If data is really valuable, store copies in a bank safe deposit box. That location may even be air conditioned to mange both temperature and humidity (check with the bank), and the inside of the box would be dark.

FYI, bank deposit box rooms tend to have a lot of magnetic fields. All that metal. So no HDDs, just optical.

Quote:

Originally Posted by dpalomaki

Test results are only good for when the test was made. A 100% test today says nothing about the results of a test 10 years form now. A 98% test today meany it is very unlikely you will get a higher test in the future (unless the problem was with the drive used to do the test).

That's not necessarily accurate. The tests themselves are dependent on the drives. Even Datarius testing equipment can vary with age, and ever unit to unit. Consumer drives are more volatile. So you really have to aggregate multiple tests, and have an intimate understanding of the test equipment. Even then, there is room for interpretation.

Quote:

Originally Posted by dpalomaki

Different media will age/deteriorate at different rates and the rate will depend on the environment, the chemistry of the media, the quality of the media, and the physical stresses to which the media is subject. And some media and burners are much better than others ...
There is no way anyone here can predict what the results with your burns will be in 10, 20, 40 years with any degree of certainty.

Yes.

Quote:

Originally Posted by dpalomaki

Time to stop asking the same questions in hope of getting a different answer.
- If having a good copy is important to you, test your burned media periodically
- Be sure to have back-up copies in a secure location.
- Track changes in test results to individual pieces of media.
- When you start to see recoverable error rates rise, consider making a new/replacement copy before the errors become uncorrectable.

Yes.