In this article, we tried to address the critical and highly anticipated in the optical industry issue of quality of a recordable DVD disc. The test procedure was simple enough and with selected measurements for each disc, chosen so as to indicate the quality of a recorded disc, hopefully in a way understandable and familiar to our readers.

The jitter to clock measurement, was chosen in order to provide a low-level examination of a recorded disc. The PI Sum8 error measurements, indicate the integrity of the recorded data, and reveal potential problems that can manifest themselves which can make a disc harder to read or even unreadable over the course of time. POF errors, are undoubtedly the most serious errors, since they represent uncorrectable errors on the recorded media.

However, have in mind that the correlation between actual loss of information and the measured maximum PIE actually depends on several factors including the playback system as well as the media quality.

A future update of this test would require additional measurements for each disc. Measuring HF Signals such as I14/ I14H, resolution (I3/I14), I14 Modulation or Asymmetry. Servo and tracking errors such as the DPD Amplitude, DPD Asymmetry would also help determine the condition of a recorded disc.

As a last note, we should say that is is not wise to directly blame either a disc or a burner when a measurement is out of specs. Along with the various parts, the hardware makers develop the software that controls the recording procedure (recording strategy) and the media makers develop recording materials (organic/inorganic dyes, phase change, etc) and manufacturing technologies that conform to the specifications and the requirements of hardware. Of course, hardware is usually built and tweaked by using the disc as a reference, or vice versa. As a result, the combination/interaction of burners and media is the factor that decides the final quality.

In this test, we tried to give an idea of which is the most suitable burner/disc combination. Of course, not all MIDs have the same characteristics, which are dependant on the manufacturing process and the materials used. Let's skip this factor for now, and assume that the MIDs show consistent results.

In the end,, all we really want from a disc is that it should be readable, not only now but also in the long term.

CDRInfo will continue to provide detailed measurements of optical media in the future.