I'm creating this thread mainly to have a handy link. There is some info about this topic in the FAQ, but not enough to my taste when I want to direct someone to some relevant reading.

For most regulars here, there is nothing new in this first post, but for many newcomers some of this info will come as a surprise, due to the huge amount of misinformation about this on the net.

Discussion is of course open, and don't hesitate to suggest corrections: I may myself have some misconceptions, or I may have forgotten some relevant info

@Arachne and Dragemester: after discussion and corrections, this post could maybe be appended to the MEDIA FAQ, what do you think?

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A persistent Internet myth, apparently instigated by online shops, is that the mediacode (also called ADVINFO or MID) of a disc (TYG02, MCC 004, RITEKG05...) only refers to the dye used when making the disc, as if the mediacode was merely the name of a given dye.

WRONG.

A correlated misconception seems to be that brands make their own discs, using this or that "dye" in the process, and that this dye used is the only difference between discs in terms of characteristics.

WRONG.

These misconceptions often lead to confusion when discussing media quality, because those who have been extensively exposed to these myths, and those who know better, often take some time to realize that they're not referring to the same thing when talking "dye" or "mediacode"!

Here is the truth:

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1. Most brands don't make their own discs.

There is actually a stunningly little number of discs manufacturers compared to the huge amount of brands available.

Examples :
Memorex, Ridisc, Datawrite, Rimedia, have never made any optical disc. They just put their brands on blanks they buy from a manufacturer.
TDK, Fuji, Sony, Maxell, Ricoh have been making their own discs for quite some time (this has changed recently).
The majority of discs available on the market are actually made by CMC, Ritek and Prodisc (Taiwanese manufacturers), or Moser Baer India. The other manufacturers have much smaller market shares.

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2. The mediacode refers to the specific model of the disc and its actual manufacturer.

This includes the dye indeed, but also the reflective layer, the type (+R/-R), the manufacturing technology, everything. Even the polycarbonate used!

Examples:
TYG02 refers to Taiyo Yuden 8X -R discs. Even if you find this mediacode under the Verbatim, Datasafe or Plextor brands, these discs were actually manufactured by Taiyo Yuden in Japan, with Taiyo Yuden technology.
MCC 02RG20 refers to Mitsubishi Chemicals (MCC) 8X -R discs. Even if you find this mediacode under the Datawrite or Infiniti brands, these discs were actually manufactured using Mitsubishi Chemicals technology by one of the authorized MCC manufacturers (though to add to the confusion, Mitsubishi outsources the actual manufacturing to other companies' facilities, but that's another story).

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3. A same dye may be used by different manufacturers to make different disc models with different mediacodes.

A manufacturer producing/formulating a given dye may sell this dye (or its formulation and manufacturing process) to other manufacturers.

Example: RITEKM02, which used a Mitsubishi dye, the same that Mitsubishi themselves used for MCC 01RG20. But the manufacturing technologies and mediacodes were different and, despite sharing the same dye, these discs were pretty different in their characteristics and each needed to have its dedicated burning strategy in the burner's firmware.

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4. The purpose of the mediacode is mainly to tell the burner's firmware how to burn the disc.

A burner firmware has burning strategies (burning speeds, methods like CLV or CAV, laser power..) for most disc models existing on the market, assuming the manufacturer of this disc model provided the necessary info and samples to the companies making the burners.

This is one of the reasons why there are faked mediacodes around. Some manufacturers (mainly in Hong-Kong) don't have (or don't want to develop) the necessary resources to provide the burners makers with the info and samples so to have a dedicated burning strategy in the burners firmwares. So they use a mediacode from another company to fool the burner (and, incidentally, the customer).

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Now that you know the truth, spread the knowledge, and don't hesitate to bother the online shops by telling them they are wrong and they are spreading misconceptions

I forgot the important "Discs with the same MID, even when genuine, are not necessarily of the same quality" point.

Upcoming

Some comments and extra's. (copy paste style, so screw ups are possible from my hand )
Let's use this comment for a building up for a good FAQ part or wiki part. If we can get the wiki back. Or if we create a new one !

Not only the online stores do this. Infact quite some online stores just use what there distributer says !!. So it's the distributers/brands (like E-net) which have caused this mayor screw up !

The reality is a bit different. Based on the licensed production were one licensee makes something with a slightly different material as another and were it behaves different on some drives. Still everything is inside the specified standards of the original technology supplier.
Specified according to the technology supplier, According to the drive manufacturer not specified enough, because they suddenly have to change there super optimized strategy that works for one licensee but doesn't perform that good for the other.

Incorrect. RITEKM02 is based on FUJIFILM02. Unless ritek doesn't know what they are using. (Well they claimed that was the case when they used some dye that infringed a patent of Ciba !,so we can't rule it out. )


That's the reality for quite some burners. However there is quite some more info in the ADIP which will specify how the disc should be burned.

Nice extra example.
Let's take the old Memorex PhilipsC16.
It uses Fuji oxolife dye
It is designed by Philips
It is made by CMC.
It is branded by Memorex

Does anybody manufacture media with Organica 16x DVD dye?

This is really useful and has answered any remaining questions I would have had.

It would also be useful to list brands which are known to -use/have used- fake mediacodes, if a thread doesn't exist already.

http://club.cdfreaks.com/showthread.php?t=112854 (for Taiyo Yuden fakes)

I would add a link here to their copious section on different brands with their variety of media codes.

Make it sticky, master Francksoy.

Thanks for the contributions guys
Too busy right now to include corrections and ideas and ask a mod to edit the post (@_chef_: hey, it's been about a year that I'm not a mod anymore, I can't make it sticky )
I'll be back!

Sorry, I wasnt sure about the current mod status.

I think that the information contained in the 7 pages here at digitalfaq.com:
http://www.digitalfaq.com/media/index.htm
has to be linked to here.

And especialy this page:
« Advanced concepts of blank DVD media quality »
http://www.digitalfaq.com/media/advancedconcepts.htm

nice work mate

enjoyed the Write up

Recently I have been able to read this on cdfreaks:
http://club.cdfreaks.com/showthread....89#post1902754
So because we have some of the main experts posting here in this thread,
could you please tell us what you think about this
« body of evidence suggesting that this oxonol dye is more stable than azo-cyanine »

Tricky since we don't know what he means with azo-cyanine.

I think that wilhelm means Azo dyes (Mitsubishi) or cyanine dyes (Tayo Yuden)
not a combination of both (azo and cyanine), which I think does not exist !

I thought that when it comes to DVDs, Mitsubishi (+ CMC, Moser Baer etc.) and Taiyo Yuden both use Advanced AZO, which would be an azo-cyanine dye?

That's what I thought years ago. Untill I heard from a certain manufacturer that they used a mixture because pure AZO would be to expensive !!

Assuming it is about pure azo dye's then it seems that my information suggests something different. (But I also didn't agree on that gold couldn't be used as a reflector after those EMTEC MPO gold dvd+R's kicked some serious ass in some tests. )

I am not sure at all about these Azo & cyanine dyes

But my main point is:
What do you experts think about this new Oxolife dye developed by Fuji ?




Here Fuji claims that this dye is eco-friendly and reliable long term storage:
http://www.fujifilm.ca/x14649.xml

They give more details about this dye here in this PDF document:
http://www.fujifilm.ca/documents/Fuj...Oxolife_EN.pdf

Fuji's been using oxonol-based dyes for a while, I'm not sure if there is anything really new about their 16x dye.

Ecofriendly yes.


Nice propaganda just like the MAM stuff.

A few things. Oxonol is not a bad dye. It's cheap and it's environmental friendly. Also stability is ok (when burned correctly) and power margin isn't the worst one out there and that's saying nicely how it is.

If we can go by propaganda from manufacturers a long then it's clear that MAM-A clearly is the best media out there. (We simpley can ignore reliable third party testing were their media is outperfomed by so called inferior products using inferior materials )

Thanks a lot for your opinion about this oxonol dye !


Here is the only brand I have been able to buy where I can be quite sure
it has oxonol dye:
... because it is written on the package

I have seen people saying that these Fujifilm DVD+R 16x are made by CMC in Taiwan



Could yo please explain how we can recognize other blank DVD's manufactured with oxonol dye ?

Wilhelm says here that Prodisc for example uses oxonol dye:
http://club.cdfreaks.com/showpost.ph...&postcount=180

Lots of information in this thread. Most of it is accurate (unlike digitalfaq where half is accurate, 20% is wrong, 20% is misleading, and 10% is quite strange.)

1) Memorex made CD-Rs in a plant owned jointly with Ritek.
2) The media code is issued to the owner of a stamper who submits samples to a governing body for approval. The code represents the stamper owner, the dye used, the stamper (groove geometry), the format, the rated speed, and the manufacturing process.
3) Discs manufactured with different stampers with different groove geometry and different processes can behave entirely differently even with the same dye. The dye is delivered as a powder, so the solvents and formulae, pump systems, pressures, and spin coaters make a vast difference in performance even with the same powder. The dyes that react to the 635/650 nanometer wavelength are cyanine, metallized azo-cyanine (sometimes just called "azo" or called "metal chelate"), and oxonol. There are multiple developers of these dyes.

The point above is excellent. There is no such thing as a good quality MID or a bad quality MID. The MID is a code recognized by modern drives whose cost-cutting has eliminated the ability to read the field codes on the discs and adjust themselves properly. It appears that these MID codes are used by some drive manufacturers to actually make some brands look bad for the benefit of other brands. Some great quality discs produce poor recordings on great quality drives simply because the firmware engineers failed to or decided not to support a particular disc.

So wilhelm, if I understand well you say that the media ratings at digitalfaq (first class, second class..) are not correct? Where can I find a more correct rating system then?
I use only Verbatim DVDs because I had been told they were great by someone I trust, and I am happy with these DVDs, but I would like to try some other discs... but I do not want to try crap, he he (chicken )

There's no "correct" rating system - only opinions based on experience.

Have a look at the polls in this forum which express our members' votes over the last 16 months:

Which brands of DVD media are good for everyday use?

Which DVD+R media is best for long-term storage?

Which DVD-R media is best for long-term storage?

Some brands to try:

Verbatim
Plextor (if you can get them - production has stopped)
Taiyo Yuden (only available online AFAIK)
HP (except the 16x DVD+R which i cannot recommend, but 16x DVD-R and 8x DVD+R and 8x DVD-R are good).

There is other good media, but those are the safest choices IMO.

I have not found any rating systems or methods that are accurate in determining quality. However, the rating system used by digitalfaq and the polls at cdfreaks are worthwhile in determining compatibility. They would be far more useful if they could be combined with a listing of the drive/firmware combinations that work well with a particular MID code. That takes a lot of work. Ratings based simply on whether or not people like the discs or have had success with them are typically more compatibility ratings, not quality ratings. Quality is determined by defined parameters that are difficult to test without expensive equipment.

Verbatim media are an excellent choice both in terms of compatibility and quality, but that does not mean that they will always work. If the MID codes change to signify process changes that allow 18X or 20X recording, some older drives may not work as well with them even though the quality has not changed. That's a problem all manufacturers face. Verbatim has an advantage in that they hold the patents to DL media and are a Japanese company. Taiyo Yuden shares that advantage (original optical CD-R patents). Those two manufacturers are generally the most compatible, but as drive production moves more to Taiwan, we can expect to see better compatibility with CMC (the world's largest manufacturer), Ritek, and Prodisc.