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  1. ...C O P Y L E F T JohnnyBob's Avatar
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    After many burns of DVD movie backups with ImgBurn, and more than 100 scans with Nero CD-DVD Speed, I've arrived at some conclusions about the relative quality of some popular DVD media, and the best burn speeds with my LG GSA-H55N 1.05 and Lite-On LH-20A1P KLON burners.

    -- Verbatim DVD+R DL, 2.4x, MKM001, made in Singapore (#65310):
    These are the highest quality DL media I've found. They're apparently no longer available in the USA and may have gone out of production entirely(?). My best burns are at 2.4x and 4x with the Lite-On. The LG is also generally acceptable at 4x burn speed, but I prefer the Lite-On. The LG stalls for about a minute at the layer break and those burns generally give a higher spike at the layer break in the scans. Reportedly these media can be burned at 6x too but my burners don't offer that option.

    -- Verbatim DVD+R DL, 8x, MKM003, made in Singapore (#95484):
    These are also good quality media. They burn OK at 2.4x-4x-6x-8x with either the LG or Lite-On. I prefer the Lite-On because it has a smoother burn strategy, especially at the layer break. They will also burn at 10x and play OK, but with less-good scans (higher PIF spikes). IMHO they are not quite as high quality as MKM001 made in Singapore. PIF totals are consistently low with MKM003, but PIE totals are generally 2x to 3x larger than with MKM001 made in Singapore. [This should also settle that particular question: My scans indicate they're different media, not just relabeled MKM001's.]

    -- Verbatim DVD+R DL, 2.4x, MKM001, made in India (#65310):
    These are 2nd class media with a 5-10% coaster rate. It's easy to see why... Some have visible blemishes, small spots in the dye which kills the burn at that point. There are also frequent irregularities near the outer edge, so the chances of getting a full 8.5G burn is dubious. After many burns and scans, clearly the PIE totals are 10x-20x larger than with MKM001 made in Singapore! Some of the PIF totals are also extra-large. It doesn't seem to matter what burn speed or which burner is used, and mostly depends on luck of the draw (quality of the individual disc). On the positive side, all successful burns (the ones that verified) with these media played OK.

    -- Taiyo Yuden DVD-R, 16x, TYG03:
    I've burned a lot of these and never had a coaster, which says something important about their reliability! After a lot of burns at different speeds with my two burners, clearly the best and most consistent results are at 16x burn speed with the Lite-On. That runs contrary to the popular notion that slower burns are better. Not so, if scans with Nero CD-DVD Speed are an indicator. Apparently some of the newer faster drives burn best when running near their maximum speed. I also have good scans of my test burns at 18x speed, but 20x was a bit too fast (poorer quality scans).

    -- Playo DVD+R, 16x, MCC004:
    I picked up several 60-disc spindles of these on special sale because they were dirt cheap. If they didn't work, not much would be lost. They have the Verbatim MCC004 media code and have given me a low coaster rate and acceptable quality scans, although there are some irregularities near the outer edge so they may not accept a full 4.7G burn. According to my scans they're not quite as good quality as the TYG03 above, usually giving somewhat higher PIF spikes and PIF totals, but they're still decent. They burn OK with either of my burners at 4x to 16x. I've settled on burning them at 16x with my Lite-On. I use them for unimportant tasks.

    I'd also like to dispel a rumor that LG burners are better than Lite-On burners. Not so, in my experience. I've used both, a lot, and after analyzing my burns extensively... I now burn everything with my Lite-On. It generally gives better quality scans, and seems more reliable with both DL and single layer media. I keep the LG primarily because it's an excellent ripper/reader of marginal/scratched/damaged discs. The Lite-On often finks out with CRC errors in such cases, but the LG will usually complete the job (apparently sometimes going into PIO mode, if necessary).
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  2. Mod Neophyte Super Moderator redwudz's Avatar
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    With some cheaper media like the Playo, I suspect the quality may vary by batch or even within a batch. Consistency between batches seems to be higher with the better brands. Some members report good results with very cheap brands, but they may not be able to repeat that with the next batch.

    I notice you don't list Verbatim DVD-5's. Have you done the same tests with them? Generally, TY and Verbatim are listed among the higher quality media.
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  3. ...C O P Y L E F T JohnnyBob's Avatar
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    Originally Posted by redwudz
    I notice you don't list Verbatim DVD-5's. Have you done the same tests with them? Generally, TY and Verbatim are listed among the higher quality media.
    I've always used TYG03 and am stocked up til the end of the year. I've never bought any Verbatim brand single layer discs, but might try them sometime. I noticed some of their good scans on the forums.
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  4. Member oldandinthe way's Avatar
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    No reason to quarrel with your media observations. They are probably valid for the media you tested and the drives you used.

    No reason to quarrel with your decision as to how you partition your process between drives for the media you use.

    I do feel your conclusions about whether LGs are superior or inferior rippers and burners rely on faulty generalization from a small sample of media.

    One of the reasons I and some others feel that LGs are superior burners is the large number of different mediaIDs which LG can burn to completion. You have tested just a few.

    The reason that others suggest LG is an inferior ripper is the fact that they have experienced disks which can be read on other drives which cannot be read on their LG drives. I too have experienced disk which rip on other drives but will not rip on LG drives unless they have been cleaned. So I suspect there is indeed some difference in the reading ability.

    The fact that you have seen your LG drive go into PIO mode to read a disk the Lite-On fails on is suggestive of a software difference. That change is controlled by the driver.

    Appears that your scans of disks written on the LG are performed on the Lite-On. The validity of such scans is not universally accepted. Furthermore, if you are correct that the LG is a superior reading drive, one would expect inferior scans on the Lite-On. OSTA an industry group questions the validity of scanning as a measure of compatibility.
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  5. ...C O P Y L E F T JohnnyBob's Avatar
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    I recall reading an anecdote somewhere in the past that LG drives are better burners than Lite-Ons, so I wanted to help dispel that rumor. My Lite-On is a better burner of both single layer and DL discs. My LG is a much better ripper of marginal discs. Those are their main advantages, in my experience.

    I didn't mention it, but used a LG 4167B for about a year before getting my current drives. I only have a few sample scans, but looks like it burnt better than my current LG model. However it had the same problem as my Lite-On; it finked out much too easily when ripping/reading marginal/scratched/damaged discs. My current LG H55N is the best ripper/reader of marginal discs I've ever tried.

    My Lite-On and LG appear similar as to available burn speeds for different media types. However this LG H55N model won't burn a MKM001 at 2.4x speed! What happened to it? It appears in the list of available speeds via MCSE, but doesn't show up in ImgBurn, so it isn't allowed. I've asked but never got a straight answer about that inconsistency.

    I have no other way to compare burned disc qualities except by using Nero CD-DVD Speed or similar softwares. I'm just beginning to get a feeling for it, and believe it's probably a valid method. The interpretation and analysis is tricky and requires proper perspective. For example I understand that DVD players read at 1x speed when playing a movie, whereas my quality scans are done at 4x speed. If I did my quality scans at 1x speed, I would probably find very few PIE and PIF (don't know, haven't tried it). So the kinds of PIE and PIF variations I'm seeing at 4x scan speed are extremes, well above the threshold where they really matter as far as playability goes. Maybe they're an indicator of longevity, at least, because I understand that PIE tends to change into PIF over time.
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  6. Member oldandinthe way's Avatar
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    There is no way to reliably measure burned disk quality except one to one on the same drive. And if the drive doesn't scan you are only left with data verification (which is unreliable due to the robust ECC on DVDs).

    A burned disk which scans well on one drive may not scan well on another and may not be compatible.

    Scanning disks is just a pasttime which stimulates your mind. It is not a measure of succesful burning, media quality or drive quality. Individuals who think otherwise are at odds with the manufacturers of drives and media.

    I don't post such comments on CDfreaks where most of the scanners hang out because I don't need to gore anyone's ox. But I do try to prevent anyone else from getting sucked in unless they realize its just a hobby.
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  7. ...C O P Y L E F T JohnnyBob's Avatar
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    Originally Posted by oldandinthe way
    There is no way to reliably measure burned disk quality except one to one on the same drive. And if the drive doesn't scan you are only left with data verification (which is unreliable due to the robust ECC on DVDs).

    A burned disk which scans well on one drive may not scan well on another and may not be compatible.

    Scanning disks is just a pasttime which stimulates your mind. It is not a measure of succesful burning, media quality or drive quality. Individuals who think otherwise are at odds with the manufacturers of drives and media.

    I don't post such comments on CDfreaks where most of the scanners hang out because I don't need to gore anyone's ox. But I do try to prevent anyone else from getting sucked in unless they realize its just a hobby.
    I disagree.
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  8. ...C O P Y L E F T JohnnyBob's Avatar
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    Some typical examples follow...
    MKM003, Lite-On 8x
    MKM001, made in India, Lite-On 4x
    MKM001, made in Singapore, Lite-On 4x
    TYG03, Lite-On 16x
    Playo MCC004, Lite-On 16x

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  9. ...C O P Y L E F T JohnnyBob's Avatar
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    MKM001, made in India, Lite-On 4x

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  10. ...C O P Y L E F T JohnnyBob's Avatar
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    MKM001, made in Singapore, Lite-On 4x

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  11. ...C O P Y L E F T JohnnyBob's Avatar
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    TYG03, Lite-On 16x

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  12. ...C O P Y L E F T JohnnyBob's Avatar
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    Playo MCC004, Lite-On 16x

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  13. ...C O P Y L E F T JohnnyBob's Avatar
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    I'll also post some typical examples of scans of burns done with my LG drive, for the same media, if anyone is interested. Or you can take my word for it, that the Lite-On burns better. Or you can argue that my theory and knowledge is naive and all wrong.
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  14. Originally Posted by JohnnyBob
    ...... Or you can argue that my theory and knowledge is naive and all wrong.
    Sometime ago I made myself a promise to never discuss quality scanning or PIE/PIF testing on any forum at VideoHelp.com and you're forcing me to break that promise. You are not going to find many sympathetic opinions here. With that said, let me state that I have spent a considerable amount of time over the last 3 to 4 years evaluating and comparing optical drives and this does include scanning in respect to jitter, PIE, PIF and TRT's. I don't find your theories necessarily naive or wrong but on the other hand they aren't exactly mature or correct either. I find quality scanning helpful for evaluation of one media vs another on a given drive model or comparing one version of firmware vs another (for example) BUT using it to rate quality of one burn over another is a hard sell even to the most avid scanning experts. Let me give you an example; a TYG03 scan with total PIF = 500 vs a TYG03 with a PIF total of 2000. Both exhibiting perfect TRT curves (performed on an extremely picky reader). One has 4 times the PIF but two years later they both perform flawlessly when read. Which is better? I can't honestly state the lower PIF value burn is better because they both play perfectly and TRT without issue. I think home scanning has its place and is valuable as a predictive tool but not as a definitive quality tool. I admire your zeal and passion - KEEP on SCANNING...

    Now some random comments:
    Originally Posted by JohnnyBob
    I'd also like to dispel a rumor that LG burners are better than Lite-On burners....... I didn't mention it, but used a LG 4167B for about a year before getting my current drives. I only have a few sample scans, but looks like it burnt better than my current LG model.
    Not surprising actually - not all LG's are created equal. You're comparing a Renesas chipped LG (4167B) to a Panasonic/Matsushita chip based drive (H55N). I've always much preferred the Renesas based drives for burn speed, performance and reliability. Good luck finding an ide/eide pata Renesas based LG on the current market. Nothing released since the H42/H44 models that I know of except sata models.

    I do encourage you to keep testing and exploring rather than taking my opinion or anyone elses. Good luck and have fun in your quest.
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  15. ...C O P Y L E F T JohnnyBob's Avatar
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    Thanks. Here's one of my worst scans in terms of total PIE and PIF, but the disc plays fine. My understanding is that if PIE spikes are under 280 and PIF spikes are under 8, the disc will probably play OK on most DVD players. That is true in this case, at least.

    So does that negate the importance of PIE and PIF totals? I don't think so. It just means that the threshold of readibility/playability is a lot different than these 4x quality scans produce. But I doubt anyone would voluntarily burn discs with high PIE or PIF totals, if they could avoid it, because from what I hear (haven't proved it, yet), these PIE and PIF data tend to increase with time. So it may make a difference re longevity of the burns, 1-3-5-10 (or whatever number) of years in the future. That's important.

    Basically, I fall back on the argument that there's no better way, of which I'm aware, so I'll probably use it til something better comes along. I believe it's better than nothing.

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  16. Originally Posted by JohnnyBob
    Thanks. Here's one of my worst scans in terms of total PIE and PIF, but the disc plays fine. My understanding is that if PIE spikes are under 280 and PIF spikes are under 8, the disc will probably play OK on most DVD players. That is true in this case, at least.

    So does that negate the importance of PIE and PIF totals? I don't think so........
    Understand I'm not trying to be argumentative. I just want to give you some "food for thought" examples to broaden your thought processes. I've got an example from a couple years ago that is perfectly applicable to discussing your quote above. I purchased what at the time I thought was the "Holy Grail" of media. I had about 200 TYG02's that in my mind were exceptional. I was a scanning fanatic at the time and these things routinely scanned with total PIF below 100. Didn't matter what I burned them with, when scanned on a 6th generation Lite-on (165P6S or 165H6S) they were excellent. Perfect TRT's on every drive I tried them on. My wife, much to my dismay at the time; violated my special stash and used about 30 or so for video contest entries by her students. I was even more annoyed when she had the audacity to complain that Contest Judges implied there were playback issues with this media in several situations. Already upset by the inadvertent loss of my SPECIAL media I set out to prove how wrong these judges were to her and prove their idiocy. I burned 4 TYG02's - 2 each on a Pioneer 108 and an LG 4163B. Both of which at the time seemed to love this media based on quality scan results. These 4 discs were scanned dozens of times each on several Lite-ons and Benq's. Never once exceeding a total PIF in excess of 150. All TRT'd perfectly on all drives tested. Here's the kicker, 2 of the 4 routinely experienced minor playback glitches on over a third of the players we tried them in. My point is that lower PIF is no guarantee. Definitely something to strive for but other factors come into play here. I personally prefer MCC 02RG20 (8x DVD-R) over TYG02 any day for video use and I assure you it will not scan nearly as pretty as TYG02 but it's reflectivity properties gives much better universal compatibility. Again - IMO.
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  17. Member oldandinthe way's Avatar
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    Harken to the words of onesickpup.

    His experience is why the industry says scan results are not a predictor of compatibility.
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  18. ...C O P Y L E F T JohnnyBob's Avatar
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    Onesickpup: Thanks again for your comments. Consider me broadened. I'm open to the idea that reflectivity is an important factor in media quality, which I've heard before but without any scientific evidence or measuring tools/software. Anecdotal evidence is fine, but I need more to turn my wheels in that direction. I will google etc when I find the time, and welcome any leading references.

    I would make one slight argument involving standalone DVD players... I've tried quite a few in recent years and 2/3rds of them were defective. That's from Walmart, Kmart, and Sears. I've currently got 3 onhand that have been tested and I know work OK, and in the process of acquiring them, returned 6 defective units. They skipped and froze, had weak audio, and did all sorts of strange things. My point is that a DVD player must first be tested thoroughly before drawing any conclusions about disc quality while using it.
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  19. Member oldandinthe way's Avatar
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    The DVD standards are very loose for media and drives. This was deliberate to allow many vendors products to qualify.

    The testing requirements for DVD writers to wear the appropriate logos is limited to a single standard media for each type.

    Some manufacturers test many different media, some do not appear to. This is why industry groups have been encouraging greater testing of drive/media pairs.

    Anecdotal evidence is what is principally available. The major problem with anecdotal evidence is attempting to actually define the conditions associated with the testing. And to avoid generalizing from any testing such as yours.

    Specific anecdotal evidence is often tainted by issues which relate neither to media quality nor drive quality.

    Tests of a drive which whose firmware does not have a write strategy for a given medium are only valid to the owner of that particular drive with that firmware rev. using the identical media.

    Test of varying burn speeds of a drive with a given media may be tainted by improper configuration of the system - no DMA, 40pin cable when an 80 pin cable is required, inadequate memory, CPU speed, CPU loading.

    Tests of a particular brand of drive with a given media may or may not be influenced by the actual choice of materials in the media, or may be a result of poor quality control. They can also be affected by enviornmental conditions, dust, temperature or humidity.

    It is hard to live in a world in which everything is relative but the only constant you can depend upon is that the identical media (this batch not any other) will perform consistantly in the identical drive assuming every thing else about the system and enviornment remains constant.

    The fact that some media manufacturers maintain a consistant product makes this easier to live with. The fact that when the same media is manufactured in different plants it performs differently may not be a sign of lower quality, but simply a change in the characteristics of the product which affects SOME drives.

    The only consistant measure of quality for the total enviornment is whether your equipment can write media which can be read on the rest of your equipment and continues to read with time.

    This can be scientifically valid, even if no one else shares your experience and it disagrees with anyone's quality rankings.

    Quality rankings are useful, because they provide a predictor of whether a large number of scientifically uncontrolled enviornments will be likely to burn succesfully.

    So when someone with an elderly drive tells you he gets great success with TY or any other specific media, burning at half the rated speed, you should interpret this to mean that he gets great success by burning with TY or other specific media, burning at half speed.

    When you have problems you can seek the source of the problem and remedy it, if possible, or you can try changing your media and/or burn speed. If the problem is crosstalk in a 40 pin cable, cutting the burn speed might clear the problem. Similarly for a heavily fragment HDD too slow a CPU, an overload CPU, or thrashing due to inadequate memory. Changing the media or the burn speed might also compensate for an under powered laser. I'm sure you get the picture.
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  20. ...C O P Y L E F T JohnnyBob's Avatar
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    Again, if there are scientific references re reflectivity as an important factor in media quality, I'm all ears. Otherwise, I presume there are none, but will google a bit when I can find the time. At this point, it sounds like Nero CD-DVD Speed and similar software are the best we've got.
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    There are not only references, but the % of reflectivity required is written into the DVD-Video spec itself.

    oldandintheway -- As much as I can admire the willingness to be a participant in a conversation, you've seriously go to detach yourself from the undeserved adoration of LG. Statements like "the standards are very loose" is not at all an accurate statement. Neither is insistence that disc quality can only be tested by the same drive in which is was burned. It's good to know that you're not bamboozled by the myth of scanning=quality, but you're limiting yourself in knowledge by hugging that LG drive so tightly.

    Scans have limited value. Use them to back up other tests, don't make other tests back them.
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  22. Member oldandinthe way's Avatar
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    Originally Posted by JohnnyBob
    Again, if there are scientific references re reflectivity as an important factor in media quality, I'm all ears. Otherwise, I presume there are none, but will google a bit when I can find the time. At this point, it sounds like Nero CD-DVD Speed and similar software are the best we've got.
    You've got nothing other than your data on your combination of equipment and the media you have tested.

    If you continue to repeat these scans, eventually the data will change. Then is your LG dying? your Lite-On dying? or the media turned to crap? If you substiute another drive you will not know if is the drive or the media. If you substitute different media you still won't know.

    Science is not possible with this technology.
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  23. Member oldandinthe way's Avatar
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    This has nothing to do with LG drives. There is an LG drive in the OPs test system hence the involvement. Others have challanged his conclusions. I have not. I have identified their limits - the OPs systems.

    Lord Smurf you conveniently forget that OSTA says exactly what I do - you can only test the quality in the drive it was written in.

    The media specs are full of + or - variation. A compliant drive can be out in one direction and compliant media in another - both meet the specs and the result is inferior - hence ECC. Burned DVDs with scanning errors can still play due to the robust error correction. This is fundamental to the technology. Even scanning enthusiasts can't agree on the validity of scans on different drives.

    My outlook is far more balanced than your mediacentric point of view, and is more consistant with the industry and real world experience.

    I do not care if you use higher priced media and spend more of your life burning each disk. I just want the naive user to understand that there are alternate views of how to get successful results and succesfully making DVDs does not have to be unduly complex or painful.

    This is not an issue in which there is a divine truth which has been revealed to you and your acolytes.

    This is a case where if you find a combination of drive and media which work for you you can be succesful.
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    As long as the results of consumer-level "quality scans" are kept in perspective, I don't see anything wrong with using them. A NASA PDS test (available here) concluded that such scans can be useful for their purposes. Besides, some people just enjoy testing their disks, or feel it helps them improve on their burning technique. Like everything else, different people have their own ways of doing things, and you should use what works best for you.

    The inherent limitations should be kept in mind, though.

    The tests are actually measuring the interaction between the drive used for testing, and the media being tested. The results show how well the drive was able to read the disk, not the absolute quality of the disk.

    Consumer drives were never designed to be used as scientific measurement devices. They use cost-effective components to stay competitive in the marketplace, with a resulting variance in performance. To offset the variance, consumer drives rely on error correction algorithms to take up the slack. That's not a problem because the DVD standards include vigorous error correction capabilities.

    On the other hand, since a scan is only showing the amount of error correction the drive reports it needed to do a successful read... is a "bad scan" the result of the media's quality, the burner's capability (with that media, with that firmware), or the reading drive's ability to read the media? To be honest, there's no way of telling for sure which part is to blame with the equipment we consumers have. A "bad scan" can, however, give a ballpark estimate of a disk's useability. It doesn't necessarily mean that the disk isn't readable on other drives, but it does indicate that it didn't work so well on the drive you tested it with, so you might want to check its' playback on other devices...reburn it...toss it...whatever you think best.

    It may sound like I'm just being negative, but I don't think that's the case. Rather, this post is based on my belief that in order to effectively use a tool, you have to understand the tool...which includes knowing its' limitations.

    By the way, the specifications for reflectivity on a dvdr (single layer) call for greater than 45%. For dual layer, it's greater than 18%. I'm not aware of any consumer level way to measure reflectivity though, so having the numbers probably won't help much.
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  25. Member oldandinthe way's Avatar
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    Thank you VegasBud.

    Why is it so hard to understand that these tests show what they show and generalization from them is not possible?

    Since you haven't mentioned a drive maker, perhaps your message will get through. At least you won't be accused of having a emotional tie to your burner.
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  26. ...C O P Y L E F T JohnnyBob's Avatar
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    Thanks lordsmurf and VegasBud for your helpful comments.

    There are not only references, but the % of reflectivity required is written into the DVD-Video spec itself.
    I've seen this mentioned several times, but without any references so it can be verified. Can someone please give me an online link(s) to that reflectivity-related information? Thanks.

    Consumer drives were never designed to be used as scientific measurement devices.
    I believe a consumer drive can be used in a scientific manner if the variance in behavior is clear, such as by control tests or prior experience with the drive. It is the person and the design of his experiments which decides whether a scientific method is being used.

    ...is a "bad scan" the result of the media's quality, the burner's capability (with that media, with that firmware), or the reading drive's ability to read the media?
    I believe it's usually the disc at fault, provided that the drive is working properly in general and scans other discs of the same type OK. This is easy to verify in some cases. To wit, a large PIE/PIF spike(s) at the end of the burn (in the 4.2G-4.7G outer limit area) probably signals correctly that the edge of the disc has imperfections, which are often visible. Similar large spikes elsewhere in the burn probably also correctly indicate disc imperfections, and the scan can be repeated for verification. Smaller variances are of course indeterminate.
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  27. Originally Posted by JohnnyBob
    Thanks lordsmurf and VegasBud for your helpful comments.

    There are not only references, but the % of reflectivity required is written into the DVD-Video spec itself.
    I've seen this mentioned several times, but without any references so it can be verified. Can someone please give me an online link(s) to that reflectivity-related information? Thanks.
    I'm not in the office nor at home (travel day) so my research sources are limited but try googling any of the following combinations of search syntax:

    audiodev +reflectivity
    audiodev +birefringence

    Or just go to this link at AudioDev: http://www.audiodev.com
    They have many technical whitepapers published and available for download somewhere on their site. AudioDev is one leading source of professional optical industry test gear. Also try searching on "dvd specifications for read only disk" or something to that effect (going on memory now). Good luck.

    On a side note - please don't perceive my posts as challenges to your beliefs/theories as has been possibly suggested in another post. I am not negative at all in regards to home scanning. I still scan to this very day for certain specific purposes. As VegasBud stated earlier, just keep things in perspective.
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  28. Video Restorer lordsmurf's Avatar
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    You won't find "links" to some "official version" of this information, as it requires NDA and is guarded information. What you are going to find are folks you understand the spec and can comment on it without quoting reference (thus breaking NDA, a severe legal issue).
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  29. Originally Posted by lordsmurf
    You won't find "links" to some "official version" of this information, as it requires NDA and is guarded information. What you are going to find are folks you understand the spec and can comment on it without quoting reference (thus breaking NDA, a severe legal issue).
    Very true. Never seen anything but references made to it - comments about it - discussion of it. Pretty much all you'll find.
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  30. Member
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    JohnnyBob,

    As I mentioned earlier, the reflectivity specifications aren't going to do you much good, since there's no way for you to measure reflectivity with consumer devices, but since you're interested, here are two ways I would suggest:
    1) Download Ecma-267 (also known as ISO/IEC 16448) available here. Look in section 12.6 on page 15. "Type A" is single layer - single side disks, and "Type C" is dual layer - single side disks. If you really want all the facts on reflectivity, you can also dive into Annex D (page 47).
    2) Download wp_DVD_dual_layer.pdf (available here). Table 1 details reflectivity for single or dual layer disks.

    I'm afraid you can't perform scientific studies, and expect scientific results, without appropriate scientific equipment. Reference drives (and entire testing systems) were developed for the task because consumer level drives just aren't suitable. Datarius has a series of whitepapers (available here) that give a good idea of what's required to run scientific tests on media. In particular, I would recommend reading the "Demystifying the drive" whitepaper.

    There are also web pages available that compare the use of consumer level testing with dedicated test systems. Here's one that has graphs that clearly demonstrate the differences. If you want more, I'm sure Google would be happy to point you in the right direction.

    Once again, I'm not trying to dissuade you from doing your testing. I'm just trying to help you use the tool(s) as effectively as possible.

    For the record, I wholeheartedly agree with lordsmurf that NDAs are a pain in the backside. Sometimes you have to accept second hand leaked versions of what's in the specifications, which is less than ideal, but necessary.
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