The aim of this review was to provide the results of media quality measurements performed with both a professional and non-professional equipment. Technically speaking, it really isn't wise to compare the measurements produced by a professional test system such as the DaTARIUS Analyser with those provided by a common off the market drives and PC application such as KProbe. The reason as we saw in all the results of this review, is that the latter lacks the sensitivity and accuracy.

The drive used in the DaTARIUS Analyser is calibrated regularly, leading to consistent measurements, something that is not possible with a PC drive. On a home brew PC system, the drive, no matter how good, will with time degrade in performance. Another factor is that with different drives, totally different results will be produced.

When testing a DVD disc, the reader produces an analogue HF signal, which is then processed using techniques that are highly reproducible. Although our aim may be to ‘test’ a disc when doing electrical measurements on optical media, what we are really measuring is how the drive interacts with the disc. If the drive itself introduces additional noise or defects to the analogue HF signal, these could easily be misinterpreted as a disc problem. This is a common problem with home-made DVD quality scans. The key design requirements for drives are specified in the physical format specifications for DVD, and it is critical that the drives used have a very high level of reproducibility – with the absolute minimum of variations between samples.

If the drive characteristics are not constant, then it will not be possible to have a reproducible test system to accommodate and correctly measure DVD burning quality. To do this, close attention has to be paid to the quality and consistency of the drive’s component parts and the consistency of key elements such as the actuator, optical components, laser diode, etc. A high quality of mechanical stability, especially from the spindle motor, is also required –especially for the higher rotational speeds.

We tried to keep test conditions constant in all our tests. Also, we selected the 4X speed for testing with KProbe because this value is used by many users when performing media tests at home, and also it is closer to the speed used by the DaTARIUS Analyzer (2X).

- The Results

The majority of the media measurements performed with the DaTARIUS Analyser, showed error level which were much higher than those produced by KProbe and the LiteOn LH-20A1P drive. Most of the times, the maximum value measured by KProbe, was equal to the average produced by our professional tester. There were times when the graphs for both PI and PIF errors, produced by both testers followed the same trend. But this was the exception and on most occasions, while Kprobe reported a perfectly good disc, the DaTARIUS system showed significant problems. Inconsistency issues are obvious here.

While a non-professional setup can sometimes provide us with information on where the error levels peak and where they are at a minimum, they can not give us a true image of the disc's quality. Most of the discs, while exceeding the error rate limits in the DaTARIUS test, were shown to have negligible errors with KProbe. Keep in mind, that exceeding the error limits does not make the disc unreadable by an optical disc drive, it just shows us that an increased level of digital errors are present, which can lead reading errors. Nevertheless, there were a few cases in which the measurements with KProbe approximated those of the DaTARIUS Analyser. While the difference between the two systems was expected, it was not possible to find a relation between the two ways of testing media.

In the future, we are going to expand this review and add tests with more burnings, drives and speeds, as well as other non-professional software such as CDSpeed.