Optical Media Longevity Stress Tests
Last updated 17th April 2022
In 2010 I started some stress tests of optical media - CDR and DVDR. The results both surprised and disappointed me. For important stuff I had always been careful to use "well known" brands that I thought I could trust. It turns out that my trust was misplaced. Some very well known brands made discs that failed after only 3 weeks, and another brand that I had not previously trusted made a disc that was still readable after 18 months (the test was stopped before the disc failed).
My first test started during 2010, lasted for almost 2 years, but only tested 3 discs chosen at random. I then started another larger and more thorough test starting mid May 2012, which has also ended.
During the summer of 2018, I started a 3rd test, using a new batch of discs with a wider range of technologies, including Blu Ray discs and MDISC discs. This test has also finished, and the results are posted below.
The test consisted of placing the discs label side down, on an interior south facing window ledge, so that on a sunny day, they will be exposed to approximately 6 hours of direct sunlight.
I performed a test read the discs every 2-8 weeks, so that when a disc started to fail, I was able to assess the lifespan of each one.
I will have no idea exactly how many hours of direct sunlight the discs have been exposed to, and although the test is perhaps a bit arbitrary, I believe it to be valid because one of the most important stress factors in everyday use will be exposure to daylight. Some testers leave discs outside exposed to the weather, but this is not how discs are normally stored, so I do not think such a test is particularly useful. However, for a disc that has failed after only 24 days, this means that the number hours of direct sunlight that has caused the failure could possibly be as little as 12days x 6hours = 72 hours.
When examining the discs that have failed, there appears to be two factors causing the failure: (1) fading of the dye, and (b) "bubbling" of the reflective layer which causes it to separate from the plastic layer. The "bubbling" effect I assume is caused by the heat of the sunlight. The bubbling effect has only appeared on a small numbers of discs - the majority have only been affected by dye fade. Below is a photo of the test arrangement; the reason for the card covering half of each disc, is to see to what extent visible fading of the dye layer correlates with failure:
Results from my tests are now available, and I have posted the results below. In the table, Date refers to the approximate purchase date, Colour is the dye/reflective layer colours and intended to help identify the dye type and reflective layer type, the Label description is colour and identifying names or text on the label side. I have omitted the dye colour for DVD-R because they are all the same - purple. Regarding the shorter lifespan of DVD-R: the good news is that I have a collection of well over 1000 discs, dating back to around 1998, and have come across very few failures so far (although I have not tested them all). Those failures have been due to:
(a) the burner/drive that was starting to fail (and I did not notice at the time), and
(b) the use of poor quality inexpensive discs.
I have recently tested Verbatim BD-R and MDISC DVD-R discs. I have no plans to test any of the following discs: dual layer, rewriteable, eraseable.
Conclusions:
1. If you need best possible lifespan, I recommend BD-R MDISC, DVD-R MIDSC. Although Verbatim (standard) BD-R also performed exceptionally well in my tests, I do not recommend it because the manufacturer does not guarantee long lifespan.
2. To minimise the effects of daylight, discs must be kept in near or total darkness. This is essential for DVD-R and CD-R discs.
3. There is extreme variability in the lifespan of CDR discs. Some tests of Verbatim CD-R discs have lasted 18-24 months without failure, but results like this are very much the exception.
4. There are no brands or manufacturers whose entire output can be trusted.
5. Higher cost price is not a guarantee of long lifespan.
6. The lifespan of DVD-R appears to be worst of all, at an average of only 4-8 weeks in direct sunlight.
7. Providing discs are kept at normal room temperatures, in darkness (i.e. in a box with a lid), then the practical lifespan of good quality DVD-R discs appears to be at least 10 years.
8. Verbatim "Archival Gold" DVD-R, is no better than the average Verbatim DVD-R lifespan.
9. If you intend using CD-R discs for archival purposes (e.g. audio CD), I strongly recommend performing a "direct sunlight stress test" on two discs from the batch. Then only use that batch of discs if both test discs can withstand a minimum of 18 months of direct sunlight. Once you have found a batch that has passed the stress test, keep that batch for archival purposes only, and not for "everyday" use.
Optical Media Stress Test Results
Here is a summary of the results. Some tests have been omitted, because they were redundant.
Verbatim BD-R
Colour: Silver
Date: 2015?
Lifespan: at least 2 years! Disc did not fail - still readable at end of test.
Verbatim MDISC DVD-R
Colour: Silver
Date: 2015?
Lifespan: at least 2 years! Disc did not fail - still readable at end of test.
Verbatim CD-R
Colour: Cyan/Silver
Date: 2007?
Label description: "Super Azo Crystal Datalife Plus" shiny silver lettering on shiny silver.
Lifespan: at least 18 months! Disc did not fail - still readable at end of test. However, note that not all Verbatim CD-R perform this well, and it is impossible to predict performance of a particular batch without testing.
Verbatim DVD-R
Date: 2008?
Label description: "Verbatim" shiny silver lettering on matt silver
Lifespan: 8 weeks
Sony DVD-R
Date: 2011
Label description: "Sony DVD Accucore" shiny silver lettering on white. Looks exactly like the DVD+R below.
Lifespan: 6 weeks
TDK CD-R
Colour: Dark Cyan/Silver
Date: 2003?
Label description: "TDK CD-R74 Reflex Ultra" blue lettering on white
Lifespan: 3 months
TDK DVD-R
Date: 2004?
Label description: "TDK DVD-R 1-8x DATA/VIDEO". White lettering on light grey/blue.
Lifespan: 11 weeks
Philips CD-R
Colour: Cyan/Silver
Date: 2003?
Label description: "CD-Recordable all speeds". Pink lettering on silver.
Lifespan: 11 weeks
Memorex CD-R
Colour: Dark Cyan/Silver
Date: 2000?
Label description: "CD recordable 74 min 650 MB" blue text on matt silver
Lifespan: 11 weeks
Fujifilm CD-R
Colour: Green/Silver
Date: 2003?
Label description: Shiny silver lettering on matt silver.
Lifespan: 19 days = approx 3 weeks
Infinity DVD-R
Date: 2004?
Label description: "Ininity DVD" plain white
Lifespan: test1=24 days, test2=4 months [two tests done]
Comment: following the suspiciously short lifespan of the first test, I did a repeat test. I will leave the reader to decide the significance of the two results... however it is possible is that the disc used in the first test was kept under less than ideal conditions prior to the test, and hence had some degradation before the test was started.
The tests have now been completed, and no further tests are planned.
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