DVD Writer or Blu-Ray Reader/Writer For Reading Bad DVD's?

vbimport

#21

Yes. The scuff marks are just inside the outer edge of the disc.

I am presuming that these scuff marks are not affecting the reading of the disc, as the disc is read starting from the inside out. The problem reading the disc seems to be from near the beginning of the second layer which, I think, also starts from the inside of the disc. The disc is also not full, it has not been written to full capacity (8.5 GB).


#22

[QUOTE=meeshu;2784350]Yes. The scuff marks are just inside the outer edge of the disc.

I am presuming that these scuff marks are not affecting the reading of the disc, as the disc is read starting from the inside out. The problem reading the disc seems to be from near the beginning of the second layer which, I think, also starts from the inside of the disc. The disc is also not full, it has not been written to full capacity (8.5 GB).[/QUOTE]

On most discs, the first layer is read from inside to out, then the second layer is read from outside in. (Sweep out, then sweep back in). This is OTP…Opposite Track Path. Makes it easier to have a seemingly seamless playback, since the drive does have to pause playback to refocus on the second layer.

There are a few discs (PTP - parallel track path) which require the drive to sweep from inside to out, then move the read head back to the inside and sweep from the inside to out again. (This would obviously require a longer pause, which isn’t optimal for most use cases).

It is entirely possible to be able to read the first layer of a disc without issue (easier to read), only for the second layer to effectively be inaccessible because of an issue at the edge of a disc. The same thing happens when burning DVDR DL media (if the entirety of the second layer isn’t rubbish).


#23

[QUOTE=meeshu;2784350]Yes. The scuff marks are just inside the outer edge of the disc.

I am presuming that these scuff marks are not affecting the reading of the disc, as the disc is read starting from the inside out. The problem reading the disc seems to be from near the beginning of the second layer which, I think, also starts from the inside of the disc. The disc is also not full, it has not been written to full capacity (8.5 GB).[/QUOTE]
As Albert said, the second layer usually starts towards the outer edge of the disc (where the first layer ended). If you do a quality scan of the DVD using one of your Lite-On drives and software such as Opti Drive Control, CD-DVD Speed, or DVDInfoPro you should be able to get a clearer picture of where on the disc the problems are located.

I very strongly suspect that those scuffs are the problem. They don’t look “very light” to me, and I don’t believe that trying additional drives will ever substantially improve your ability to read the disc. I’m surprised you didn’t mention them at all two weeks ago when I originally asked about the disc’s condition.

The scuffs should be buffed out, ideally professionally, but you are of course free to try common DIY alternatives such as toothpaste or Brasso at your own risk. If you go the DIY route it would be a good idea to experiment/practice on a disc you don’t care about first.


#24

The scuff marks seem to appear worse in the photo than they are, and I wasn’t overly concerned with these, at least not initially anyway.

The concern is more to do with the “distorted” not quite circular pattern of burnt data on the disc (the change in tone indicates burnt area of disc), as this suggests some issue with the media (deterioration?). Normally, the burnt data is seen as perfectly cylindrical pattern of tone change without any distortion.

Determining the physical location of the errors on the disc using various software is proving to be difficult, as the software just say the errors occur from about 55% of total written data onwards. But where is that 55% physically located on the disc?

I’ve tried Opti Drive Control, Nero DiscSpeed, and VSO Inspector so far to determine where the errors are located on the disc, but these programs don’t actually indicate where the errors are physically located.

However, I thought there was a program which did indicate physical location of bad sectors on a graphical representation of the disc. Any ideas?

By the way, the scuff marks on the disc are suspected to have been caused by my standalone DVD player while playing the disc and during an earthquake. This would probably have caused the disc player to jump about a bit causing brief player optical scanner head contact with the disc.

All my discs are handled carefully and always stored in their original cases.

As far as cleaning the DVD is concerned, I can’t afford “professional” services to do this, so I will have to try a home remedy instead.


#25

This isn’t a burn DVD, though, so that area of random discoloration isn’t representative of where the data exists. It does indicate that the disc maybe wasn’t made quite perfectly.

How much data is on the disc? Can you try to do a transfer rate test with OptiDriveControl & upload the image?


#26

Yes. Strictly speaking it is a “pressed” disc. But the gist of it is that to have a variation/inconsistency in tone on the disc suggests a problem with the media.

The data occupies 5.86 GB on the 8.6 GB dual layer disc.

Screenshot of transfer rate test using ODC is attached.

The test was done without decryption/de-protection programs running, if that makes a difference.

Also, ODC screenshot save function didn’t save a complete image of the test results for some reason. I had to use Windows screenshot instead.

Note that there is quite a substantial amount of data (approximately 700,000 sectors worth) that is not readily readable!



#27

If I am gauging this correctly, 4 GB is the very edge of the disc. So it makes use of all of layer 0, and only part of layer 1.

For it to start reading layer 1, then falter after advancing a bit, then pick back up, points more at the scuffs than the uneven coloration. But, given the proximity of the issue, it’s hard to tell.

See if you can’t find a way to buff out those scuffs, because they certainly are doing you no favors, I can guarantee that.


#28

Good news and not so good news.

Most of the scuff marks have been removed using the “toothpaste” cleaning procedure. After that, the disc was able to be copied (via IsoPuzzle) to near completion, when IsoPuzzle decided that the copying was finished with 1081 missing sectors still to be processed!?

The resulting ISO file was played back and it was found that there was still some pixelation and slight video image distortion remaining here and there. So the ISO copy is not a perfect copy of the disc. Not happy with that.

So, I’ve started copying the disc once again via IsoPuzzle from the beginning. This time the number of initial “missing sectors” reported by IsoPuzzle had been reduced to around 370,000, compared to around 700,000 missing sectors from earlier scans before removing the scuff marks.

Unfortunately the read progress on the missing sectors is slow, despite using several different drives (LiteOn iHAS324 C, LG GGW-H20L, and Samsung SH-224GB). Currently the number of missing sectors has been reduced to around 198,700.

So there still seems to be an issue with reading data off this failing DVD. Since most (if not all) scuff marks and any smudge marks have been removed, this suggests an issue with the media itself being faulty (deterioration?).

Back again to finding a better drive for reading failing data(?)


#29

Plextor PX-755/760 drives can do great things reading warped discs (great tilt control). And mine once managed a bona-fide miracle - extracting secure audio from a CD with a deep, completely circular scratch.

But they aren’t particularly good with other defects (although my experience is mostly with CDs not DVDs).

An NEC-based Pioneer or Optiarc (AD-7200 or later) may be worth trying. Or a Renesas-based drive, such as a Pioneer BD writer or older LG DVD writer.


#30

Thanks for the comments.

I was looking at getting an older model Plextor drive, but based on comments posted in this thread, it seems they may not be good at reading (non-scratched) bad discs. Since my disc is almost scratch free (apart from extremely minor scratch marks near and at the periphery), an older(er) model Plextor drive would most likely not be able to read the failing data very well.

I have an Optiarc AD-7200A drive, but it does not read failing data well, at least not the data from this particular disc I have. I just tried reading the cleaned disc using the Optiarc drive (on another computer), but on first pass the drive failed to read about 680,000 sectors! I then tried a Toshiba SD-H802A drive, which picked up a few more sectors on the first pass with the number of missing sectors reoprted by IsoPuzzle reduced to around 600,000 -.

Then tried an Asus DVD-E818A9T b drive which dramatically read many more sectors, with the number of missing sectors reduced to around 360,000. Finally tried a LiteOn iHAS324 B drive which picked up a few more sectors for a total of around 350,000 - missing sectors remaining.

I’m looking at an older model LG drive, but I can’t really afford to buy it (or any other drive) until I’ve sold some or all of my other drives that I have for sale.

In the meantime on my main computer with the LG GGW-H20L, LiteOn iHAS324 C, and Samsung SH-224GB drives, the reading of the failing disc has progressed slowly with the number of missing sectors down to 163, 843 (only! :rolleyes:;)).


#31

I haven’t used IsoPuzzle before, but have you tried IsoBuster.


#32

IsoBuster has been tried (on other discs). If IsoBuster can’t read data (properly), I believe it replaces the unreadable data with zero’s(?) to make up to the original file(s) size. The problem is that the “recovered” data is not the same as was on the original disc because unreadable data was replaced with zero’s. This means that the copy will not play back properly. This is not what I want to happen.

If set up properly, IsoPuzzle will try indefinitely to retrieve all data from a disc. This is what I want. I don’t want (other) recovery software either skipping bad/unreadable sectors and/or filling in unreadable data with zero’s (or whatever else) as this will make the copy not play back properly.

Currently down to 127,254 missing sectors, but the rate of return is diminishing. The full content of the failing disc might not be fully recovered (using my current drives)?


#33

Wouldn’t it be simpler just to buy that disc again (if it’s still available and reasonably priced)?


#34

It would be easier to get another disc. Problem is this disc is part of an old TV series disc set which was released about 9 years ago, and it is not possible to buy a new or even a used disc anymore. I’ve looked online and haven’t found any of these discs for sale.

The advantage of finding good “bad DVD” reading drives now is that I have a few other discs which are starting to fail also. I want to back these discs up as soon as possible using these good DVD reading drives before it is too late.

Down to 103,425 missing sectors now on the failing disc.


#35

An update.

Thought I would try the LG GH24NSD1 writer to read the remaining missing sectors from the failing disc. The LG writer finished reading the failing disc fairly promptly, but suspiciously finished reading maybe a bit too quickly!? My suspicions were confirmed in that the resulting ISO file had pixelation and other video image problems when played back.

Tried reading the disc from the beginning using only the GH24NSD1 writer. The writer read the disc fairly quickly although slowed down while reading in the failing areas of the disc. The resulting finished ISO image on playback contained even worse pixelation and other image and playback issues!

So, the LG GH24NSD1 writer is NOT recommended for reading failing data as the writer does not seem to read (all of) the data correctly!

Back to using just the LG GGW-H20L, LiteOn iHAS324 C, and Samsung SH-224GB writers to try to read the disc again. :sigh:

Actually the GGW-H20L and SH-224GB writers seem to be doing reasonably well at reading the failing data (after cleaning off (most) scuff marks). And the SH-224GB seems to be a bit better at reading the data than the iHAS324 C writer (at this stage)!

Presently down to around 162,130 missing sectors from approximately 400,000 sectors after initial disc scan using the SH-224GB.


#36

I think all of the drive you have mentioned are Mediatek-based (except for the GGW-H20L which appears to be Renesas).

My experience of optical disc data recovery is confined to CDs. But when trying to retrieve usable audio from badly damaged discs what usually made the difference was having access to drives which used different makes of controller chip inside. A Mediatek-based Samsung would perform similarly to a Mediatek-based Lite-On (despite different OPUs), so it was rarely worth trying both. An NEC-based Optiarc on the other hand would generally be outperformed by the Mediatek drives, but it was sometimes able to read the one section of audio the Mediateks couldn’t.

So if you are looking for other drives to try, I would suggest trying to find a modern NEC-based drive (Optiarc, Pioneer) and a Panasonic-based drive (some LG drives).

In this country such drives can be found on Ebay cheaply (often <£5 inc. P&P, sometimes even new).

I find this database very useful when trying to identify which controller a drive uses. Different families of controller usually have the same read offset (e.g. +6 for Mediatek, +48 for NEC). There are some anomalies - such as later NEC-based Pioneers being +96 - so it is desirable to cross-check elsewhere when it matters.


#37

Comments noted thanks!

Very interesting information!!

Yes, I am aware that some chips used in drives may perform better than other (brand) chips. But drive performance would be dependent on the firmware also, I believe(?)

Actually I have been wondering whether there is/are software that will identify the chips used in optical drives without having to physically open up drives for visual inspection of chips?

Now considering several options for other drives, based on comments within this thread.

Down to 143,110 missing sectors on the bad disc. Currently using the iHAS324 C.


#38

[QUOTE=meeshu;2784574]
Yes, I am aware that some chips used in drives may perform better than other (brand) chips. But drive performance would be dependent on the firmware also, I believe(?)[/quote]The latter may be true, but that doesn’t mean the reading capability of a drive is changed. There are quite a few cases where a manufacturer puts out an update relating to how certain types of discs are read (or detected in the first place), but you shouldn’t expect a significant performance gulf in general, especially when reading a disc that is optically distorted.

Now when different manufacturers use the same chipset, THAT’S when you’ll catch a different ability to read. That may also be down to the optics & other factors, though.

Actually I have been wondering whether there is/are software that will identify the chips used in optical drives without having to physically open up drives for visual inspection of chips?
No. There is no such ability to query the drive for that kind of low-level information. The data would have to be stored in a database elsewhere. For most of the popular drives of the past 8 to 12 years, you can use a swift Google search and find out which chipset is inside.


#39

Noted. Thanks.

An update on drives used to read the failing DVD. The order of the drives have been revised after a bit more “testing” in trying to read the failing DVD.

Ordered from best reading drive first, with the worst performing drive last. Note that drives are listed in approximate order, especially for drives within the middle of the list.

LiteOn iHAS324 C, firmware LL14, chipset Mediatek MT1809LN

LiteOn iHAS124 F, firmware CL99, chipset Mediatek MT1862N

LiteOn iHAS324 B, firmware AL14, chipset Mediatek MT1839LN

Samsung SH-224GB, firmware SB00, chipset Mediatek MT1862AN

LG GGW-H20L, firmware YL05, chipset Renesas R8J32702SFPV

Asus DVD-E818A9T b, firmware 3.00, chipset ???

Plextor PX-891SAF, firmware ???, chipset Mediatek MT1862N

Toshiba SD-H802A, firmware HP10, chipset Toshiba TC94A68FG

Optiarc AD-7200A, firmware 1.09, chipset NEC MC-10043

Pioneer DVR-215, firmware 1.22, chipset NEC MC-10042

LG GH24NSD1, firmware LG00, chipset Mediatek MT1862AN <- unreliable in copying failing data

Currently down to 75,620 missing sectors. Was using the SH-224GB drive, now using the GGW-H20L drive. Will switch back to the iHAS324 C drive shortly as the GGW-H20L drive is struggling a bit to read remaining missing data.


#40

[QUOTE=meeshu;2784611]
Asus DVD-E818A9T b, [I]firmware[/I] 3.00, [I]chipset[/I] ???
[/QUOTE]
+6 read offset, so should be Mediatek as well. -Rom drives are almost invariably less good at reading than writers.

Interesting results. Not surprised that the Mediateks beat the NECs. The poor performance of the (Mediatek-based) LG seems to confirm a suspicion that recent LG models are pretty junky. Shame, they used to make such good drives.

If you are using your drives intensively (especially if the optical pickup is moving backwards & forwards a lot re-reading) they can get extremely hot inside, which can cause the drive to fail. Also, they don’t seem to read as well when hot. (Learnt that lesson while trying to extract audio from damaged CDs.) If possible, try to let the drive pause and cool down every 15-30 minutes. And/or maybe use the drives in rotation.