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But a difference of 100x on total number of C1 errors is not an issue of inexact results. How can a difference of THIS magnitude be explained?
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I tend to be more concerned by jitter than the C1/C2 errors. Same goes for DVDs. The jitter is often more telling than the drive's error reporting.
Home based testing is simply an analysis of how that exact drive is reading that very disc, and at that one time. If you don't want to believe us, then you can refer to the white papers released by DaTARIUS on this topic -- where they say the same thing, but with more words (mostly jargon). DaTARIUS makes actual reference/testing drives.
You can re-scan the disc tomorrow -- or even 10 minutes later -- and have different results. Sometimes it's a small change, sometimes it's quite drastic. Out of the last 40 discs I scanned, I came across one disc that scanned different each of 3 times.
There may be a weakness in that drive's ability to burn CDs, or read them back. I honestly would not doubt it. The Pioneer DVR-109/A09 drive was lousy at burning CD-R. (Drives before, and since, have more or less been fine. It was just that one subpar model for CD performance.) The LG burners in my laptops ignore already-burned CD-R, write them badly, and can only acceptably read/write DVD with any reliability.
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I have an older highly rated BenQ (1655) that I am considering putting in to replace the LiteOn.
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That is a good drive, yes. I use the 1620 still, which doubles as a test drive for partial/quick analysis.
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However, I gotta find an adapter (IDE-SATA], not easy here in Thailand.
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This usually does not work. Those converters are made for hard drives. Optical drives will perform poorly or not at all. You need a native SATA burner for a SATA connection. Or IDE for IDE.
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It is clearly labeled as AZO. It also said "JAPAN" but the small print says "made in China." Disk ID says only Verbatim, no other company. The metal layer is gold-colored and the dye side is pale blue.
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That describes Azo media.
Note that the "Japan" refers to Mitsubishi Kagaku Media, while the "made in China" is the country of origin where the product was made. Many countries require country of origin be put on packaging, by federal/national law. (Mostly N.A. and Asia, not so much in Europe, hence the issues with Eastern European counterfeit goods.)
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In Thailand, Taiyo Yuden CDs are impossible to find. To order it by mail would nearly double the price. It is possible, but not easy, to find TY DVD-R.
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TY media isn't really sold locally outside of Japan. It's mostly sold online, worldwide. And it can be more costly, and for good reason -- it's basically a specialty disc made in a premium-priced country, and subjected to import/export tariffs.
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These verbatims were roughly double the cost of any other CD-R, roughly $12 USD for a 50-pack. So this price is clearly in the ballpark you suggest.
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When Verbatim Azo media were still widely available, that was the price here, too: $13 USD in local stores like OfficeMax (when on sale) or online from
Amazon.
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That works fine if you only need the CD for a month. I am VERY concerned about a longer life. I lost a fabulous live concert recording when the CD gave out. I would not spend the extra money for Verbatims unless I had some reason to trust its life span more than a Sony, Imation or TDK.
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The idea that a disc will die on it's own is mostly myth. Poor handling kills probably 95-99% of all discs -- such as scratches, storing in sunlight, storing in non-archival locations (basements, cars, attics). Stored and handled properly, discs don't simply have data "disappear" as some would lead you to believe. That's just not scientific.
Very often, it's a case of scratches that are too tiny to see with the naked eye, but are obstructing or refracting the microscopic laser (mere nanometers).
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I am HIGHLY skeptical about this claim for DVDs. How sure are you? If you have the evidence, I may use those Taiyo Yuden gold DVD-Rs to store my ISO, RAR and ZIP files.
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This is easy to test. Get a disc you don't want, get a coin, and scratch the hell out of the top of the CD. You've ruined it. Repeat this on a DVD. No effect. You've pretty much have to beat it with a hammer to damage the platters. (Do note that putting undue pressure on a DVD, however, can still affect the internal foil/dye, or the glues, so again test with a disc you don't want!)
The CD-R is structured as such:
-- label surface (optional)
-- lacquer
-- sputtered foil (reflective for laser)
-- dye
-- thick base polycarbonate
i.e. -- ZERO protection on the dye. The sputtered foil and lacquer are both about as thick as a woman's nail polish. Scrape on it a little bit, and it's all screwed up. I've had CD wallets rip the foil and lacquer off a disc. Yes, the case ruined the disc. (One of MANY reasons to never use wallets!)
A DVD-R / DVD+R is structured as such:
-- lacquer (and optional label surface)
-- upper polycarbonate, half-thickness of disc
-- sputtered foil reflective
-- dye
-- lower polycarbonate, half-thickness of disc
For further reasons why Blu-ray (BD-R) may not be archival:
-- lacquer (and optional label surface)
-- thick upper polycarbonate
-- sputtered foil reflective
-- dye
-- extremely thin lower polycarbonate + anti-scratch surfacing polish
It always comes back to how you can damage that dye and foil layer. CD has no protection, Blu-ray has issues on the bottom, and DVD is perfectly protected in the center of the disc layers. For a DVD, the "weak link in the chain" is the adhesives/glues used to maintain the sandwich. That's also an issue for BD-R. It did not apply to CD-R, but it's a better weakness to have.
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If the surface scan reads OK, and if the CD plays/reads OK, why the would there be such a huge difference in C1 errors between the LiteOn and three other drives I have tested?
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We're more or less left to guess. Some people will insist they know the answer, but it's just an over-confident/egotistical guess on their part.
C1 errors are generally caused during the write process, but the question comes in the accuracy of the tests.
(A) Burned disc on Liteon, discs show high errors in any drive: If you feel you can eliminate enough variables (use other discs, compare against other drives, same drive in another computer, etc etc), then maybe that exact drive -- or that whole model of drive, or even just that exact firmware -- are somehow faulty at burning.
(B) Burning anything anywhere, only testing on LiteOn shows more C1: If you merely see fault in the tests, then simply remember testing by end-user drives is mostly a drive just reporting its own self-operation, and the "quality" of a disc is just a guess on its part. In this case, it may simply be a poor reader, even if it's a good writer. That happens.
Are you below the 220 average? That's really the cutoff for good/bad (according to Red Book standards). The lower the better, of course, but you can't always rely completely on drive scans.
