Recordable Blu-Ray Disc Longevity – Periodic Survey Part 2

M. Elea (thanks for reading, and commenting) commented on my last post

Why did you do the quality scans with 8x speed and not with 4x?

I did reply on that comment, but the gist was that 4x is a speed which reduces drive influence, and I would do scans at 4x when I have the time. The main reason I chose 8x was that it was a time-saving measure, and I had been informed prior that 8x scans were close enough – apparently the current wisdom is that this is no longer the case.

After 14 massive hours of disc scanning, we have this post!

So please consult this post along with the last post (here) and addendum (here) and compare scans. The same sample discs have been used – the degradation in the days/weeks between scans should not have affected them. Scans show slight “character changes” in trends – likely to be a disc “rigidity” (outer edge), drive tracking/focus (outer edge) or dust issue (despite efforts to keep all discs fingerprint(!) and dust free). The firmware of the drive had been upgraded from HL04 to HL05, although this is unlikely to have impacted on the scan.

TDKBLD-RBB-000

Sample Disc 1

Sample Disc 2

Sample Disc 3

TDKBLD-RBA-000

Sample Disc 1

VERBAT-IMc-000

Sample Disc 1

Sample Disc 2

CMCMAG-BA3-000

Sample Disc 1

Sample Disc 2

Sample Disc 3

{Bonus Scans – these discs wasn’t part of the original set, but I scanned them so it might as well go up …}

PHILIP-R04-000

Sample Disc 1

Sample Disc 2

LGBRA-S04-000

Sample Disc 1

Sample Disc 2

INFOME-R30-000

Sample Disc 1

Sample Disc 2

MEI-T01-000 (DUAL LAYER)

Sample Disc 1

Sample Disc 2

Sample Disc 3

TDKBLD-RFB-000 (DUAL LAYER)

Sample Disc 1

Sample Disc 2

Concluding Words

So yes, one can scan at 8x, but can’t expect perfectly comparable results to 4x scans. However, interestingly, maximum BIS and BIS trends in general remained similar (but lower) between 4x and 8x scans, however LDC values were lower for the 4x scan compared to the 8x scan, and hence the average LDC value is almost halved (in some cases) when scanned at 4x compared to scans at 8x.

I won’t get into debates about which scan speed is most accurate, but it goes to show that on the iHBS212, it appears that 8x scans give a harsher indication of disc condition (especially on the TDKs) – sometimes overly harsh! It also let the MEI DL discs scan correctly! So it probably was a good idea to scan at 4x to compare with others … Interesting is the anomalous result in the INFOME discs – a chunk of elevated error which isn’t present at the 8x scan. Maybe these discs are “degrading” as we speak …

Compared to the rule of thumb for LDC/BIS scans is LDC average <=13, and BIS peaks <=8 – these discs are now closer to the LDC average requirement, but not reliably so – the BIS peaks are still in danger though.

Overall, do these scans make me trust my Blu-Ray discs any more than before? I would say, most likely not. If anything, error rate improvements have been marginal – the “room” to move in error rates is very small. I can’t say with any great certainty that it is a good long-term archival media, but I can’t say that it’s a trainwreck either. The conclusion – it’s inconclusive.

Again, I reiterate that so far, only the Ritek discs have shown sudden death over time – now, there are only 2 out of 16 Riteks in my possession that would read at ALL. So Ritek failure is real, don’t chance it. Early TDKs showed oxidation of the reflective layer at the edges – likely because of a “sealing” problem at the edges, but this is gradual and visibly detectable. The Riteks of mine show no visible sign of physical failure.

Just for kicks – the only two still fully readable Riteks scan as follows:

RITEK-BR1-000

Sample Disc 1

Sample Disc 2

Looking at these scans, yes, it’s obvious that the last 2 readable Riteks are on their way out as well. So these scans are definitely worth doing, as while these discs are perfectly readable (surprising for the 2nd disc where the lite-on just “gave up”) in the LG GGW-H20L, they are “silently” dying. It also establishes that discs with these error levels are still readable! So maybe we’re being a bit too stringent with our criteria …

Please, nobody ask me to repeat this at 2x …

UPDATE: Summary Table for convenience.

UPDATE 2: Charted for convenience, Verbatim is the stand out leader, CMC seem to be quite variable.

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8 Responses to Recordable Blu-Ray Disc Longevity – Periodic Survey Part 2

  1. Deanwitty says:

    Thank you for all the time and energy you’ve invested in helping us get a clearer picture of the value of Blu-ray as a worthy back up medium.

    It amazes me that the Ritek disc design is so poor that even with the advantage of inorganic dyes,, it degrades more rapidly than many DVD-R using organic dyes. It could also be that they are using a lower grade polycarbonate, allowing easier ingress of atmospheric corrosives to the reflective/dye layers.

    I am very sorry to see that you’ve lost so many back-ups. I was fortunate enough to run into this report on Riteks quite some time back and avoided them at all costs.
    http://www.taperesources.com/docs/falcon-ritek-bluray-performance-report.pdf
    Unfortunate that your H20L did not show one of the better burn strategies for archival life with the RBB MID in that test. That test is a nice example of how differing burners do in fact yield different archival results with BD-Rs.

    Its great to see a BD-R DL holding up reasonably well. It seems that currently there is too much speculation and not enough real info on DL longevity. Perhaps Panasonic is not stretching the truth too much with their longevity claims. Thanks for this.

    Also grateful to see the INFOMER30 holding up well. These are just starting to become more accessible in the US. And VERY tempting for bargain price shoppers.

    I know we are grateful to you over at MyCE/CDFreaks for your work. I feel lucky to have you as a partner in our effort to discover the truth about BD-R (-;

    • Gough Lui says:

      Thank you very much for your kind words. Indeed, I have not seen that report before – but I have my own skepticism about that one. It looks very “marketing” and less detailed on how the tests were done. A quick glance at the graphs didn’t seem to show the H20L having a stand-out poor performance (looks like several other burners were just as bad – although I suspected this was the case).

      It’s still early days for my INFOMER30 – I was expecting them to go the way of the Ritek as well as my PHILIPR04. They all have that brown DVD-RAM-like colour inorganic dye. For that matter, so do my RBBs – I am actually quite disappointed with my RBBs. That being said, RBBs are hard to get hands on, as TDK have been rebadging CMC stuff (and RITEK possibly) in their spindles. I’ll keep in touch via myCE (CDFreaks back in the day – old habits die hard, I liked the old name better).

      So far, I like the results of the Verbatim (with its tarnished gold/silvery layer) the best. They inspire confidence despite being reprints under a no-brand (which generally implies it’s not top-notch). Second to that, the CMCs are a bit variable, but okay as they are also somewhat old along with the RBBs. Too close to call for the other media types.

      Again disappointment with the TDK DL’s – I’ve been warned several times of compatibility issues, but I’m getting similar layer break performance from my iHBS212 and my H20L (my only burners at the moment), so I probably won’t be buying any more of them.

      I think I might actually give LGBRAS06 a go sometime soon (can be had from eBay sub$1 per disc!) for my next batch of BD-R blanks. The LGBRAS04 (with its horrid reputation around CDFreaks – I bought them at $10/disc) fared pretty well in my tests with a dark grey-ey sort of bottom layer. The fact that someone mentioned it was manufactured by ISMM really was a big shock. I’m just as apprehensive about ISMM as for INFOME (which I bought when being sub$2 was a bargain) – in the DVD days, they were pre-coastered out of the box!

      Right now, I’m giving a RBB a scan – pre and post clean – this one is a pristine burnt-and-packed with no testing before – I’ll let you know how that goes on CDFreaks.

      For those following at home – here’s where the discussion is.

      • Gough Lui says:

        As another note – upon performing several cleans on discs, I have found that the results can be “improved upon” – rather surprisingly. Maybe next time I will clean my discs even better – although there were no visible signs of dust or smudges, something must have interfered with the scans somewhere along the line.

  2. Chris Walker says:

    I’ve been testing Blu-Rays by leaving in the sun. I tested Ritek BR3, Verbatim BA5, and the DVD Verbatim MCC004. Ritek BR3 appears to die in 16-30days of summer sun exposure, while Verbatim BA5 will last the entire summer. DVD will only last 2-3 days.

    Leaving them in the sun, also exposes them to rain and dew. It becomes apparent that the plastic membrane that covers the data layer is very thin, and will breach with a very shallow scratch. Quickly, it will peel off. This membrane alone, and the seal at the edge, will decide longevity.

    The reasons for your variability is not just smudges on the disk, You cannot scan for 14 hours. My LG reader caves in, after it gets hot, after 3-4 fast (12x) reads. It would have to be cooled by fan, in between each disk.

  3. Michael says:

    If you want to know which media to rely on for backup there’s a french study conducted by the french ministry of education and cultural affairs which is very enlighting.
    An english summary and the report (in french, but the graphs speak for themselves) are available here:
    http://www.cdrinfo.com/Sections/News/Details.aspx?NewsId=34515 and here
    http://www.archivesdefrance.culture.gouv.fr/static/6187

  4. Pingback: Recordable Blu-Ray Disc Longevity – Periodic Survey Part 3 | Gough's Tech Zone

  5. steve says:

    What software do you use that makes those graphs? How much does it cost? – thanks
    Steve – Dallas

    • lui_gough says:

      The software is called Opti Drive Control and is available for $24.95 USD, however, it will only work with certain drives. Also note that different drives will give slightly different results, there is some debate as to the validity of scans done with certain drives at certain speed combinations.

      Recommended are Lite-On Blu-Ray Burners, although noting the 312 seems to be less harsh than the 212, and the 112 seems to have been used by many early scanning efforts. Unfortunately, as hardware continues to evolve, I’m not sure what the best options are in today’s market.

      Most other drives (e.g. LGs) have no ability to produce LDC/BIS scans whatsoever and can only perform a readback check using CD-DVD Speed (by the same author, formerly packaged with Nero).

      – Gough

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