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An Introduction to DVDScan v0.04 for LiteOn drives

General discussion about recordable CD, DVD and BD media and write quality testing.

An Introduction to DVDScan v0.04 for LiteOn drives

Postby MediumRare on Sat Jul 15, 2006 6:01 pm

There's been a lot of action at CDFreaks the last while with 2 LiteOn employees (Wind and Tom) contributing test firmware versions with new capabilities (Hypertuning, Online Hypertuning, etc) and a new toy, DVDScan, that can do various kinds of disc diagnostics. I think these things really add to the value of newer LiteOn drives and would like to share some of my experience with them, primarily with DVDScan.

I've tried to add a short description of what the various tests measure. Please note that this is my understanding of the subject- I'm a physicist and not a technical expert on optical drives.

Since the LiteOn guys are doing this on their own time, please share any insights and experience with them. They monitor and contribute to 2 threads at CDFreaks:
New Toy: DVDScan and Feedback Here:
Online Hyper Tuning Test Firmware and Results here:

DVDScan:

Image

What is DVDScan
DVDScan is a disc analysis tool written by a LiteOn employee Tom (Wind acts as his spokesman in addition to his work on firmware). It offers various diagnostics for DVD media:
  • PI/PIF with PI or PISum8. This reports the activity of the error correction
  • Jitter and timing analysis, describes the variation of the lengths of the pits and lands from the ideal values
  • Beta (asymmetry of short and long pits/lands)
  • TE/FE (tracking error and focus error)
Although CD and BD are shown as disc types, neither is supported at present. The tool shows the MID of the DVD medium inserted.

What is required
To run DVD-Speed you need:
  • the program (:wink:)
    The newest version will generally be linked in the first post in the CDFreaks thread New Toy: DVDScan and Feedback Here.
    An early package didn't include the file IEEE_32M.DLL, but the mirror at CDFreaks now has it.
  • a newer LiteOn drive, generation 5S or 6S (look at the last 2 digits of the model number), e.g. SHM-165P6S
  • a firmware version that supports the tests.
    At present this usually means a test firmware as supplied by Wind (a very communicative LiteOn employee). To get the newest flavours available, see the thread Test Firmware ANNOUNCEMENTS.
    Owners of the 1635S and 165P6S are fortunate in that the lastest official firmware YS0Z and MS0P supports these tests. These are also available at the codeguys website.

Updates
The latest version as of this writing is v0.04 Beta (21 Jul. 2006). Here the change log:
I released DVDScan v0.04 beta to Liteon pals 3 hours ago. There are some features modified.
1. Support measuring 1 of 4 drives.
2. Annoying habit of ESC key was disappeared.
3. PI/PIF Total using sum values instead of count values.
4. RealTimeChart could be disabled in PI/PIF test. So you can get higher sample count.
...
the (point) (comma) problem not yet modified.


Apart from the PI/PIF scans, I didn't see any significant differences in the test results with earlier versions (or between firmware MS0P and MV9N for that amtter), so there's no reason not to use the new version with it's very welcome changes!

Edits
- 15 Jul. 2006: original version of this guide. Appearence of v0.02.
- 24 Aug. 2006: update to v0.04
Last edited by MediumRare on Fri Aug 25, 2006 12:43 pm, edited 2 times in total.
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How to best use it

Postby MediumRare on Sat Jul 15, 2006 6:06 pm

How to best use it (my experience)
I've used DVDScan on all my recent burns and have checked some older ones as well. Most of the examples shown here are from a much-tested Verbatim 16x inkjet printable DVD+R disc (MCC 004 Made in Taiwan by CMC) burned @16x with my SHM-165P6S with test firmware MV94. I've checked the systematics of speed and sample sizes with other discs as well, though, and the extreme jitter examples are not from this disc.

Saving results
Since there is not (yet) a builtin capture possibility, screen shots have to be done by hand either with a capture tool or using Alt-PrtScr and pasting to a graphic tool (e.g. IrfanView). Save the image as a PNG. You get an optimal image size by resizing the window so that the scroll-bars just disappear.

A big advantage of this tool is that (in most cases) you can save the raw data to a text file as well. It's not as convenient as saving RAW data in KProbe, but it opens the door to separate analysis and display of the results.
To save the raw measurements:
- click in the scrolled results window at mid-left
- mark everything with Ctrl-A
- copy to the clipboard with Ctrl-V
- paste in your favourite text editor (I use TextPad) and save to a file.
This information is not avaialble when the Real Time Display is off.

Speed and sampling
You can choose the scanning speed in all test types. The maximum available speeds vary according to the test type: 2x (Beta), 8x (jitter and PI/PIF) and up to 16x for TE/FE. The optimal speed varies as well- more about this later.

Except for PI/PIF, you can also choose the sample interval between 400h and 10000h LBA (LBA = Linear Block Address of sectors). According to the author, this will be implemented for PI/PIF as well. The sample size is always a tradeoff: if you choose a greater interval, the test will run faster (with fewer samples) but you lose detailed information. A useful size is 1000h, which gives you ca. 560 samples on a full DVD.

The effect of the sample interval is shown in the next diagram, where my standard sample disc is scanned for jitter @4x with varying sample size. The individual curves are shifted in this Excel chart so that they don't overlap. Clearly, the shape and general trend don't change with the sample size, but more and more detail is lost when the size is reduced. The time required for the scan varies essentially linearly with the sample count: a 4x/1000h scan takes about 2.5 minutes, 400h (which is 4x finer) takes almost 10 minutes and 4000h ca. 0:40. Except for tests like these, the sampling rate generally used is 1000h.

Image

Scan range
Finally, you can pick the range of the disc to scan (LBAS and LBAE entries). Normally, this will be the entire disc- in that case, click on the Disc tab to transfer the current values.

Zooming in
DVDScan seems to use the same plotting widget as KProbe. That means you can zoom into part of the displayed data by marking a rectangle with the left mouse button. Zoom back to the full size with a rectangle that extends over the top of the plot. It's a bit finnicky, but this allows you to pick out some details after a scan if required.

Real Time Display
Normally DVDScan creates and update the display in real time, which is very nice for watching the data build up, but can drastically affect the scope of a PI/PIF scan. The checkbox introduced in v0.04 only affects the PI/PIF scan (see below), it is forced on for the other tests.

Edits
- 15 Jul. 2006: original version of this guide
- 24 Aug. 2006: update to v0.04: add description Real Time Display
Last edited by MediumRare on Thu Aug 24, 2006 5:38 pm, edited 1 time in total.
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Jitter

Postby MediumRare on Sat Jul 15, 2006 6:13 pm

Jitter

Image

Probably the most interesting test offered by DVDScan is Jitter. During a jitter scan, the tool shows momentary values for the timing analysis (you can watch them dance around if you have a disc with varying jitter). This is displayed as a series of peaks (plotted separately for lands and pits) that show the logarithmic distribution of the lengths of the channel bits (normally 2^17 = 131072 samples per jitter value, as shown in the display).

Ideally, these peaks should be sharp lines at multiples of the basic period T. Due to the 8-to-14 encoding on a DVD (data bit to channel bit), not all multiples are present. The shortest are 3T, the longest are 14T. The width of these peaks determines the jitter- the wider the peaks, the greater the jitter. This makes it clearer why a high jitter value can make it difficult to read the data: for very high jitter, the peaks overlap.

The first example shows one of the highest value I've encountered (a 2 year old burn with my SOHW-1213S): over 16%. In particular the short 3T peaks are very broad. The corresponding KProbe scan shows a pronounced PI peak at this position, which shows that the drive's error correction is somewhat stressed here- as expected. :wink:

Image

The next sample shows the well separated narrow peaks that characterize a low jitter- 8.7% in this case.

Image

The actual jitter values are plotted in DVDScan in units of 0.1%. If you compare these values to CD-Speed scans, be sure to take the scaling into account: the standard range here is 5%-15% (expanded if required), i.e. 0 is not shown. CD-Speed displays values for 0-10% (good scans) or 0-20% (when max>10%), so in most cases, fluctuations will be more evident with DVDScan. The default limit shown in the graph is 11%, but you can input your own value.

Most regulars know that the results of PI/PIF scans will depend on the scanning speed. The same applies to the jitter tests here, though the trend is not as apparent. The next diagran shows the influence of the scanning speed for the same disc as in the sampling chart. The results for 1x and 4x are very similar, the 2x results are somewhat lower and the 6x and 8x curves have a different shape. The time required doesn't vary as much as you'd expect: ca. 4 min. for 1x and 2.5 min. for 4x and faster. Most people at CDFreaks use 4x.

Image

Comparison with other drives
The most common drive types that offers jitter testing with CD-Speed are the BenQ models 1620-1655 (and OEM partners e.g. Philips). Many Plextor drives will also present jitter scans with PlexTools or Alexnoe's PxScan (but without a quantitative scale).

There have been various comparisons at CDFreaks with mixed results (which was to be expected). For example, sosotilt found very similar results to a BenQ scan, but with values ca. 2.5% higher. pchilson did some 3-way comparisons- in one case Plextor was the odd man out, in another, BenQ- but the Plextor results are "tilted" radially (they drop) in comparion to LiteOn.

Pulsee did a comparison with 3 different LiteOn drives and a Plextor. The LiteOn results do not vary more than in repeated scans with the same drive (!!) and the Plextor plot again looks similar if you correct a radial drop.

Since I don't have a BenQ or Plextor drive, I can't contribute first-hand observations on this. Watch the results threads (or do your own comparisons :wink: ) if you're interested.

Edits
- 15 Jul. 2006: original version of this guide
- 24 Aug. 2006: minor additions
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Beta

Postby MediumRare on Sat Jul 15, 2006 6:15 pm

Beta

Image

Another quantity that DVDScan can show is Beta. I don't know precisely how this is defined- it is related to another quantity called asymmetry or ASYM (Wind mentioned that Beta is about 2 times Asymmetry). The asymmetry describes the difference in the DC offset of the shortest (3T) and longest (14T) signals. The DC offset is related to the difference in the land and pit signals. If this value varies too strongly over a disc, the signal processing becomes difficult and may result in higher PI/PIF values. A good beta curve should be close to constant over the disc.

DVDScan allows 2 speeds for this measurement: 1x and 2x. 1x takes ca. 25 min., but 2x seems to be more "speed 2" than 2x because the time required varies significantly with the type of media. Here are some typical vaules for 1000h samples:
Code: Select all
DVD+R    1:55
DVD-R    5:30
DVD+RW  11:20

A DVD+RDL takes very long and only the first layer is scanned.
The curve does not vary much with the speed, although the absolute level may shift by 1-2% from run to run- so there is no point in using anything but 2x. The structures do not seem to correlate with jitter or PI/PIF in most cases- so I'm not sure how useful this information is.

Comparison with other drives
Plextor offers the only other consumer drives that offer beta testing with PlexTools or Alexnoe's PxScan. The first comparison that I saw was done by DrageMester. The results are similar: jumps in the beta value occur at the same positions, but the Plextor results have a different absolute level and seem to have an radial tilt.

A recent comparison by mognegna between Plextor 716A and LiteOn 1635S showed very similar beta curves for an 8x Plextor burn- down to the absolute values (note the scaling on these plots!). Jitter was at great variance, though, in a 3-way LiteOn/BenQ/Plextor comparison. This seems to be reproducible with his drives.

Edits
- 15 Jul. 2006: original version of this guide
- 24 Aug. 2006: added additional comparisons
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TE / FE

Postby MediumRare on Sat Jul 15, 2006 6:17 pm

TE/FE

Image

The third test parameter is the Tracking Error / Focus Error which is related to how the drive will follow radial (TE) and vertical (FE) deviations of the information track. In both cases I've looked at, the values were well within the suggested limits shown by DVDScan. This test is interesting mainly because it can be applied to discs prior to burning- it measures a property of the disc itself and not the combination disc + burn. The results do not change much after burning as shown in the attached chart.

Image

I've had problems with scanning at speed > 2x, but 2x (ca. 5:30) is fast enough for this test.

This test is not supported by the 5S drives.

Apparently Plextor drives (PlexTools) and BenQ drives (QSuite) can show TE/FE as well, but I have not seen any comparisons.
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PI / PIF

Postby MediumRare on Sat Jul 15, 2006 6:22 pm

PI/PIF

Image

This is the classical quality test that got most of us into this game- Parity Inner errors and Parity Inner Failure measure the degree to which the system's error correction mechanisms are required. These values will never be zero, but we like to see them as low as possible. The ECMA requirements (for calibrated drives at 1x scanning speed) are PIF <= 4 per ECC block and PI Sum 8 <= 280, and this has been inofficially adopted as a guidline for our home drives at higher speed as well. An ECC block consists of 16 sectors @ 2048 Byte and PI Sum 8 is the sum of all PI errors in 8 sequential ECC blocks.

In contrast to the previous quantities, there are other tools that can report PI/PIF from LiteOn drives (e.g. KProbe2, CD-DVD-Speed and DVD Info Pro), so comparisons are possible.

DVDScan allows scanning for both PI and PI Sum 8 in combination with PIF and shows most of the usual statistics. The numbers in the "PI Total" and "PIF Total" boxes have been corrected since v0.02 and now show the correct sums. (For PISum8 the sum over the PI values from the scrolled window is higher than the total shown, but that seems to be from oversampling the PI values to match the PIF points).

The PI/PIF results (all performed at 8x scan speed) look very similar to what KProbe or CD-Speed show, as indicated in the next 2 diagrams:

Image

Image

The peak in PI at 0.7 GiB is characteristic for this batch of media and shows up in every burn I've made.

The next diagram shows the DVDScan results with option Real Time Chart enabled. The PISum8 cuirve is green rather than blue to distinguish it from results without the RT chart.

Image

With this option active, DVDScan creates and update the display in real time- that is very nice for watching the data build up, but it is a big problem for the scope of the scan. Look at the total sample counts: KProbe shows ca. 120000, DVDscan without RT chart ca. 115000 and with RT chart less than 9000 - not even 1/12 this count.

That is because the drive is polled for the PI/PIF counts and if the CPU is busy redrawing the display, it can't check for the next sample in time. Ideally, the drive should deliver a PIF count every 16 sectors (1 ECC block) for complete coverage. KProbe manages this every 17-18 sectors throughout a scan at 4x or 8x scan speeds, but DVDScan starts at intervals > 20 and increases to over 600 (!!) at the end of the disc. The next chart was drawn up in Excel and shows the PI Sum 8/PIF counts and the sampling interval.

Image

Ignore the spikes- they result from other demands on the CPU, e.g. loading or using other programs during the scan.

I strongly recommend turning the Real Time Display off (you can see why Karr Wang removed the real time display from KProbe...). The one downside is that the running counts aren't shown in the scrolled widget if the RT display is off and hence cannot be copied to a text file (I would greatly appreciate an export option for the raw values here!)
The momentary values are avaialable in 2 new display boxes, however, so (like KProbe) you still get an idea of the current PI/PIF counts.

In any case, the widget is fast enough to handle the sample intervals used in the other tests (400h to 10000h) without losses- but that is not the complete coverage we've been using to now. I don't know anyone who uses CD-Speed's QuickScan option (which isn't exactly comparable) on a regular basis.

Also, at least one user has performed scans with the RT display on and sampling comparable to KProbe- but we don't know what he did right or what we are doing wrong. :wink:

In all, the PI/PIF scans have benefited greatly in the new version, but personally, I still prefer the alternatives (sorry Tom).

Edits
- 15 Jul. 2006: original version of this guide
- 24 Aug. 2006: update to v0.04. My standard sample deteriorated from handling, so a lot of the scans were redone to allow comparisons on an equal basis, The old results may be seen here: DVDScan v2, 4x, KProbe, 8x, CD-Speed, 8x, sample interval, 4x.
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Gotchas

Postby MediumRare on Sat Jul 15, 2006 6:25 pm

Gotchas and Updates
This program is definitely in beta status (version 0.04!). This doesn't mean it's not useful- quite the contrary!!!- but it's a warning to expect some loose ends and unexpected behaviour. Here are some of the "gotchas" in the present version:
  • It "only" allows a choice of 1 of 4 drives (up from 2 in the previous version). If you have more, disable any virtual drives you may have and either disable some of the additional optical drives with the device manager or reassign drive letters so that the drive you want to use comes at the start.
  • The size of the disc is not detected automatically except on startup. Be sure to click on "ReadDisc" before starting a test.
  • There is no builtin capture function for screen shots or text results. Use Alt-PrtScrn and paste to e.g.IrfanView for images and Ctrl-A / Ctrl-C to copy the text if you need it.
  • European (and other) users with a comma (not a point) as decimal mark can't do jitter scans unless they change this using the Regional and Language Options option in the control pannel.
  • The progress bar is not updated during a jitter test.
Fixed in 0.04 (the release notes are in the first post):
  • Some of the numbers were not what they seem. For example, PI Total and PIF Total were not the total PI/PIF counts. Rather, they were the number of samples with PI or PIF > 0.
  • The Esc key was blocked as long as the program is running. This was rather unnerving if working with Excel with DVDScan running in the background.

Hopefully new versions will continue to address these items! We've got high hopes that this very useful tool will continue to improve!

Thank you Tom and Wind. =D>

G
Edits
- 15 Jul. 2006: original version of this guide
- 21 Aug. 2006: update to v0.04
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Test firmware

Postby MediumRare on Sat Jul 15, 2006 6:28 pm

A couple of words about the test firmware

Although this isn't directly related to DVDScan, the test firmware offers other benefits in addition to enabling the DVDScan tests:
  • Hypertuning (HT) and Online Hypertuning (OHT) adjust the writing strategy on the fly for optimizing burning quality.
  • Overspeeding (OS) allows writing one step faster to most media (e.g. 8x to 4x media, 12x to 8x rated)
  • reading speed is 16x for single layer media and 12x for RW independent of the supported writing speed. The official firmware offers 16x reading only for media types with a 16x write descriptor.

There is a new version 3.16t of SmartBurn (the program) that optimally supports these new options. Get it here.

Image

The codeguys' EEProm utility will save and restore the contents of the EEProm and can selectively reset the stored learned media data and HT information.

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Postby Ian on Sat Jul 15, 2006 9:28 pm

I like what I'm seeing here. My only concern is that like KProbe, DVDScan is a pet project of people at Lite-On and is not officially acknowledged and/or supported by the company. If Wind and Tom leave Lite-On.. there goes the development of the tool. What would be nice is if they'd give their code to others so that this could be integrated into CD Speed and DIP.

Lite-On would be smart to advertise things like HyperTuning and write quality testing as actual features and include a suite of utilities with their drives. I've heard rumors of an actual suite of tools being in development, but I haven't seen or heard anything in awhile. Hopefully these plans weren't dropped with the Lite-On/BenQ merger. Then again, with their QSuite, BenQ could be a positive influence in this regard.
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Postby dolphinius_rex on Sun Jul 16, 2006 1:10 am

That was simply incredible MediumRare... I'm in awe of the amount of detail and time you put into that!!

I look forward to trying out DVDScan on my LiteON 1635s in comparison to my BenQ DW1650, PX-716, and a CATS analyzer late next month :wink:

Most of the info will probably be posted in the subscriber's section first however, until I can finish prepping my findings.
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Postby MonsterMan on Sun Jul 16, 2006 8:38 am

Neat tool.

Ya know, I see the same stupid PI spike on some (well, MOST) of my Verbatium media...WTF is up with it!?! It's on discs that were bought 9 months apart, shows up whether the disc is scanned in an NEC, BenQ, or Plextor, and it doesn't which of my 6 burners it's burned it at any speed!

Super annoying!

Right now, I've got a few 25-pack spindles sit aside that don't show the spike...they're my "reserved for really important stuff" discs right now...
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Postby Scour on Sun Jul 16, 2006 6:13 pm

Very informative, MediumRare :)

I´m not sure about the scan-results, whether I can compare to scans with Plextor or Benq-drives.
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Postby Bhairav on Mon Jul 17, 2006 9:40 am

Great thread, MediumRare! Thank you so much for the time and effort you put into it!

I vote for a sticky!! Ian, may I do the honours?
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Postby Ian on Mon Jul 17, 2006 12:52 pm

Bhairav wrote:I vote for a sticky!! Ian, may I do the honours?


I thought I already did? If not, go for it.
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Postby cfitz on Mon Jul 17, 2006 7:11 pm

Well done! Thanks MediumRare.

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Postby MediumRare on Mon Aug 14, 2006 5:47 pm

Just got back from vacation- thanks for all the kind words, guys. Feedback helps to keep the motivation going for exercises like this.

Ian wrote:I like what I'm seeing here. My only concern is that like KProbe, DVDScan is a pet project of people at Lite-On and is not officially acknowledged and/or supported by the company. If Wind and Tom leave Lite-On.. there goes the development of the tool.

That is very true. LiteOn IT appears in the title bar (unlike KProbe), but I don't think that means too much.

A new version (Beta 0.04) was released about 3 weeks ago, here's what Tom has to say about the changes:

I released DVDScan v0.04 beta to Liteon pals 3 hours ago. There are some features modified.
1. Support measuring 1 of 4 drives.
2. Annoying habit of ESC key was disappeared.
3. PI/PIF Total using sum values instead of count values.
4. RealTimeChart could be disabled in PI/PIF test. So you can get higher sample count.

...

the (point) (comma) problem not yet modified.

I'm working on an update to the introduction that takes these changes into account. The effects of the RealTimeChart require a new image and some updates (because my sample has suffered a bit due to handling :evil: ). I'll get those done shortly and will be in touch with Ian about uploading them.

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Updated to v0.04

Postby MediumRare on Fri Aug 25, 2006 12:57 pm

It took a while, but the introduction is now up to date as far as capabilities of DVDScan goes.

I changed the title to include the current verions (v0.04).

It's gotten better. :D (the tool, not the description).

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Postby DrageMester on Sat Aug 26, 2006 1:39 pm

Excellent work updating your guide, MediumRare! =D>

Regarding the TE/FE scans, it's my opinion that they are only useful if you scan at the same speed that you intend to burn the disc at. The TE/FE scans can be very dependent on the scanning speed. So even though you get best results at 2x, I don't think that a 2x scan will tell you anything useful unless you intend to burn at 2x or 1x.

I have LiteOn 5S and 6S drives as well as a BenQ and a Plextor, so I can make comparative TE/FE tests when I get some time. The results will be posted at CDFreaks in the DVDScan thread, but don't expect it to happen right away. :)
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Postby MediumRare on Sun Aug 27, 2006 4:17 pm

DrageMester wrote:Regarding the TE/FE scans, it's my opinion that they are only useful if you scan at the same speed that you intend to burn the disc at.

That's a good point.
I don't really know how these quantites are measured. If they rely on the feedback signals from the PUH, they may be more sensitive to variations in drive geometry than other quantities. Do you have any information on this?
So even though you get best results at 2x...

They weren't my best results- they were (almost) my only results. The tests I tried at faster speeds didn't finish but started repeating somewhere during the scan- see this post at CDFereaks. I haven't tried them since, but will do so to see if the problem persists. It may be my drive- but I really haven't seen many other scans of T/FE at all.
I have LiteOn 5S and 6S drives as well as a BenQ and a Plextor, so I can make comparative TE/FE tests when I get some time. The results will be posted at CDFreaks in the DVDScan thread, but don't expect it to happen right away. :)

I'm looking forward to that. I appreciate your insight in these matters and value your contributions highly!

G
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Postby DrageMester on Sat Sep 09, 2006 5:18 pm

DrageMester wrote:I have LiteOn 5S and 6S drives as well as a BenQ and a Plextor, so I can make comparative TE/FE tests when I get some time. The results will be posted at CDFreaks in the DVDScan thread, but don't expect it to happen right away. :)

MediumRare wrote:I'm looking forward to that. I appreciate your insight in these matters and value your contributions highly!

It took a while but now it's done.

You can find comparisons of TE/FE tests using LiteOn+DVDScan, BenQ+QSuite and Plextor+PlexTools as well as some comparisons with PIE/PIF scans on the burned discs in this new thread at CDFreaks:

Tracking Error (TE) and Focus Error (FE) testing

You are welcome to participate in that thread if you like, and so is anyone else with experience, opinions or questions on TE/FE testing. :)
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Re: An Introduction to DVDScan v0.04 for LiteOn drives

Postby s_v_dragos on Sun Jan 16, 2011 4:24 pm

For MediumRare & DrageMester, if I am not too late here, please help me with an answer.
For DVDScan, FE/TE test, what values should I choose in the "spec"s? Defaults are 80 and 60 and in MediumRare's guide - in the first image 80 and 60, but in the third, 7th and 8th (FE/TE test) - 70 and 40. These values can be changed with no warning or advice... Even at the end of the test the program doesn't offer any sentence. In QSuite's case there is a red line (you can not modify its value) for TE and a green line (the same - you can not change its value) for the FE as refrence guides - if the graphics are under those lines, then the DVD is good for burning under the chosen speed, if above the lines - not good. So what value is the reference for TE spec (80? 70? another?) and what value for FE spec (60? 40? another?) ?
And a less important question:
Which other tests should I perform for a blanc DVD?
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Re: An Introduction to DVDScan v0.04 for LiteOn drives

Postby MediumRare on Tue Jan 18, 2011 5:38 pm

Hi s_v_dragos- I'm glad someone is still looking at this guide after all this time! :D

Although I still do DVDScan tests on many DVDs that I burn (if I have the time), the TE/FE test is the one that I generally look at the least. The problems I had getting it to run while I was writing the guide haven't recurred- it's completely unproblematic. I meant to revise the discussion, but after DrageMester posted his excellent investigation, the priority went down so much that this has landed in nirvana. :-?

I've never changed the defaults for the TE/FE limit lines, so I can't help you much there. The values 70/40 were set in the first version (V0.01 beta) and were changed to 80/60 in V0.02 beta. I tend to use quality media (mostly Verbatim) and haven't seen any TE/FE scans that come near those limits. If you see high values, burn the disc anyway and check the transfer rate (CD-Speed TRT) and/or PI/PIF afterwards.

As to further tests on blank discs- there really aren't any that you can do with home equipment. A professional device (e.g. Audiodev) can check things like disc planarity, but that's out of our league. Be sure to keep your blanks clean (dust specks may leave shadows burned into the information layer that show up as PIF clusters) and keep them out of direct sunlight (UV can deteriorate the dye).

G
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Re: An Introduction to DVDScan v0.04 for LiteOn drives

Postby Ian on Tue Jan 18, 2011 7:51 pm

A better alternative to DVDScan for FE/TE testing may be Opti Speed Control (cdspeed2000.com) as its still being actively developed. The only downside is that its not free.
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Re: An Introduction to DVDScan v0.04 for LiteOn drives

Postby s_v_dragos on Wed Jan 19, 2011 7:30 am

Ian, my question was different: what value is the reference for TE and what value for FE ? Even for Opti Drive Control there are no reference lines on the graphics. Did you try it to see that? For QSuite everything was clear: reference red line for TE and green line for FE. And just a little observation about Opti Drive Control: test ends too fast (comparing with QSuite) even at at minimum sample rate (8 mb) , to be very accurate...
MediumRare, I used Verbatim too, dual-layer at 2.4X for my old BenQ and I foud 10% of DVD's not recommended to write. So ...
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Re: An Introduction to DVDScan v0.04 for LiteOn drives

Postby DrageMester on Wed Feb 02, 2011 3:31 pm

Just noticed that someone had bumped this old thread.

For me, the reference values for TE and FE values is not particularly important, since my testing showed that TE/FE testing on blank discs was not a good predictor for the PIE, PIF and Jitter on the disc after burning. There's also the fact that the only thing you can really do after performing a TE/FE test on the blank disc is to change (reduce) the speed at which you subsequently burn the disc, and I burn almost everything at 8x anyway.

So for me the TE/FE testing is simply not worth the time anymore. I burn the disc at 8x (or sometimes 6x/12 depending on burner and media), verify the content is readable at maximum speed, and perform a high-speed or quick-scan to get an idea of PIE/PIF/Jitter levels. This is enough most of the time.
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