Please e-mail me for some off-the-record info, if you are interested...

(in reply to DazaX)

Some points you may need to look at:

1. Manufacturer of the disc (read ATIP).
2. Comparing C1 and C2 error rates between discs.
3. Type of dye used (Phthalocyanine, Cyanine, Azo, Hybrid, etc.)
4. Thickness of the dye layer/reflective layer.
5. Quality of protective layer.

Discs do not burn slower of faster because of dye. The drive has most of the control as to how fast a disc can be recorded. LiteOn has the SMART-BURN feature that limits the speed of recording when media with a blacklisted ATIP code has been inserted. You can override that by disabling SMART-BURN. When disabled, you may have slowdowns due to the drive's laser collaborating with the media. That's the only reason why a disc may record slower. When a lser is trying to collaborate, the recording speed will slow considerably and is very noticeable. I suggest when doing media tests, record randomly generated data on the discs to eliminate one MAJOR variable - hard drive transfer rate.

If all goes well, all discs should record at roughly the same speed, +/- 5 seconds at the most. After you record them, do C1/C2 checks using the latest Kprobe and record your findings. For a basic durability tests, put them in sunlight LABEL SIDE UP!!! for a day and test for C1/C2 after the period under the sun. Repeat this until all discs fail and record your findings. See which disc lasts the longest!

Remember, eliminate as many variables as possible!

TerminalVeloCD
P.S. Black discs have a black base polycarbonate layer over standard cyanine or phthalocyanine dye. It makes the base more resistant to scratches but from what I've read DOES NOT contribute to quality of recordings.

(in reply to DazaX)

Terminal Velocity:

I disagree with all but 1 of your things to look at for quality.

#1: ATIP has NOTHING to do with quality, it only leads you to an idea about the manufacturer, and this only tells you about reputation. Remember, this doesn't give you any idea about the batch number and therefor could still be a good CD-R from a generally bad manufacturer, or a bad CD-R from a generally good manufacturer.

#2: Comparing C1/C2 error rates; This will give you an idea of the disc quality, but it depends on how accuratly your CD Burner returns C2 info... but generaly this is the most reliable way to test for quality, at least amongst us amateurs.

#3: Type of Dye used; Completely unimportant. Taiyo Yuden uses Cyanine, but so do many third tier companies that make pretty cruddy CD-Rs. Phthalocyanine is used by Mitsui, but also some REALLY crappy third tier factories use it as well. Azo is used mainly by Mitsubishi Chemicals, but I believe that some other companies are starting to use it now. Formazon was a hybrid, and was used by the late Kodak manufacturers, but they arenm't made anymore . Basically, every dye type CAN be good, and several are known to also be bad on occasion.

#4: I've never heard of thickness being an issue. I am aware that different CD-Rs have different thicknesses, but I've never seen any corrilation between quality and thickness.

#5: Quality of protective layer; This has NOTHING to do with burn quality, but can have a large impact on how long the quality of the CD-R lasts. You can theoretically have a really bad CD-R that is protected from degrading further.... but that won't help you if it was bad to begin with!

Sorry, I'm not meaning to knitpick, but things are confusing enough in the CD industry. If this is for a research project, then he had better stick with the bare essentials that can be verified instead of branching out into areas that can't really be helpful to him. Imagine trying to cross reference burn quality tests taking into account the Dye type. All of a sudden you have 4 or 5 sub catagories (assuming a proper range of media to begin with) and this can get very complicated.

(in reply to DazaX)

Just adding some extra info.

Quality of protective layer can influence the writing quality.
HUH You must be joking/No way, dude are some people now thinking. Well I'm not if this protective layer isn't put decent on your cd-r. You will have some slightly spinning problems which will cause a higher error ratio.

(in reply to DazaX)

quote:

---

Originally posted by TerminalVeloCD

Some points you may need to look at:

1. Manufacturer of the disc (read ATIP).
2. Comparing C1 and C2 error rates between discs.
3. Type of dye used (Phthalocyanine, Cyanine, Azo, Hybrid, etc.)
4. Thickness of the dye layer/reflective layer.
5. Quality of protective layer.

---

Trying to clarify things, I assume #1, #2 and #3 are the parameters (along with disc cost) of the tests and #2 (and possibly #5) the measures.

In case the tester can do a really considerable number of unbiased tests, then he can use some sort of an On Line Analytical Proccesing tool to get some results.

I do not know how convincing these results might be though...
Good luck.

(in reply to DazaX)

And last, but not least, please come back here soon:))))

(in reply to DazaX)

Dolphinus_Rex,

The points I brought up were possible things to look at when researching CD-R media and I agree that some of them are not by any means determinants of CD-R quality. The test that I suggested is a simple test for durability of the media, assuming the discs recorded properly in the first place. I'm assuming here that a CD that lasts long under the sun is "good value for money", therefore I believe that this test may be suitable for DazaX.

I know that ATIP codes are definetly NOT representations of quality. Every batch of discs is different. However, when doing research, I think it would be helpful if ATIP codes are given in the final report. Also, dye type is irrelevant, but like the ATIP code, it would be worth noting in the final report.

Regarding C1/C2 tests, to eliminate the variable where every drive reads C1/C2 differently, DazaX should use the SAME recorder to test for C1/C2 throughout the research project. DazaX must state what recorder was used during the research because some recorders are more compatible with a specific type of disc than others.

Complex? Not really. It's just like many of the CD tests that have been posted on the CD Freaks forum. Just post the ATIP code, recorder used to burn/read, and the Kprobe/CD Doctor chart.

As I have said earlier, the key to this and many other research projects is to eliminate as many variables as possible.

DazaX, I wish you luck in your project.

TerminalVeloCD
P.S. To Dolphinus_Rex: Keep up the good work on your website! ^_^

(in reply to DazaX)

THANKYOU VERY MUCH, ALL OF YOU!

Your opinions and thoughts are very much appreciated, thanks to everyone especially terminal velocd :).

I will be sure to publish the results after I finish the project, once again thanks :D

(in reply to DazaX)

Thanks! :-)

Also thank Dolphinus Rex, he's also done a lot both here and elsewhere.

TerminalVeloCD

(in reply to DazaX)