Within a couple of years, the Blu-ray burners have become faster and have possibly reached their limits today by offering recording at Blu-ray recordable discs at 8x (although the 12x could be also achievable in theory).
Looking back some years ago when the development of the DVD recordable format was in full progress, we can easily say that the burning speeds for the DVD+R/-R as well as the DVD+RW/-RW were gradually increased, taking quite a long period to reach today's 24x limit.
It is obvious that the Blu-ray disc and drive makers have been eager to push the writing speeds of their products in an effort to make the Blu-ray disc format more attractive to PC users, offering quick burnings of huge amounts of data stored in BD-R SL and DL discs.
The latest Blu-ray disc burners are currently offering recording speeds of up to 8x for the Blu-ray recordable discs. The question here is whether these high-speed burnings are reliable and these 8x BD-Rs will be readable over a very long period of time.
In general, the readability of a disc depends on the reading drive, which is influenced by the
resultant writing quality produced on the disc, which is in turn
directly related to the recorder used for burning
and the optical medium itself.
Today we test the quality of some of the BD-R SL and DL media after being recorded with the Pioneer BD-R 203BK and Sony BWU-300S 8x BD burners.
Although measuring the quality of a disc is complicated and requires reliable testing equipment, we needed to have a first idea of what a user should expect from a high-speed BD-R burning.
For our tests, we used the Opti Drive Control software by Erik Deppe together with a LiteOn DH-4O1S BD-ROM drive as a reader. The software offers a quality disc scanning option and reports two signals that give indications (signals) of the digital errors found during the reproduction of a Blu-ray disc. These signals provide information about
the physical condition of a disc and the integrity
of the digital data, as they are stored on the disc
and retrieved by the player. You can find more information about the test configuration and methodology in the following pages.
We are not sure that out tests will make a clear statement on the playability of the Blu-Ray media and their reliability. The Blu-ray format is squeezing huge amount of data onto 12cm
media using various techniques, so it's easy to
understand why measuring the quality of the
recorded data is more complicated when compared to CD and
The Blu-ray disc format is uses a laser with a Numerical Aperture of 0.85nm. This means that the laser beam that accesses the data is very narrow, compared to CD and DVD. As a result, the laser beam can be easily diffracted by small particles or defects that exist on the disc's surface. The size of these particles could be microscopic, as in the case of the dust or smoke. So measuring the quality of a Blu-ray disc requires extremely careful cleaning of the disc surface first.
In addition, the equipment we used for this test is actually a home brew PC system and the reader we used, no matter how good, will time degrade in performance, not to mention the fact that with different drives (readers) it is most probable that we will get different results as it happened in case of DVD testing. If the drive's (reader) characteristics are not constant, then it will not be possible to have a reproducible test system to accommodate and correctly measure Blu-ray burning quality.
Technically speaking, it really isn't wise to expect very reliable results here using a common off the market drive and PC application such as the Opti Drive Control software and a commercial BD reader, at least compared to those produced by a professional test system. However, we hope that we will have a rough idea of the condition of the data stored on a BD-R disc burned at high speeds.