Panasonic LF-D521 IDE DVD-RAM - Page 6

DVD Error Correction Tests

In the following tests we examined the DVD error correction capabilities of Panasonic LF-D521. For the tests we used CDVD Benchmark v1.21 and Nero CDSpeed . The reference test media comes from ALMEDIO.

- Single Layer media

ABEX TDR-821

This is a single sided, single layer DVD-ROM with a 4.7GB capacity, in which there are scratches with dimensions from 2.6 to 4.8 mm. The following transfer rate picture comes from CDVD Benchmark v1.21.

Panasonic LF-D521finished the task with no errors. The graph is not interrupted, meaning that the drive read the disc smoothly and no errors were reported. Apart from the defected areas, the inserted test disc is a DVD-ROM and was read at 12x CAV. The performance is high prevailing the drive's advanced error correction capabilities.

ABEX TDR-825

This is also a single sided, single layer DVD-ROM of a 4.7GB capacity. The data structure of the disc is exactly the same as that of the TDR-821, with a single difference that there are no scratches on it but defected areas with dimensions ranging from 0.5 to 1.1 mm. There are also fingerprints sized from 6.5 to 7.5 mm.

The drive did not have any problems to read the disc contents. The yellow dots correspond to the current speed in each area of the disc. No read errors were reported.

- Dual Layer media

ABEX TDR-841

This is a 8.5GB dual layer, single sided, DVD-ROM disc with artificial scratches of dimensions ranging from 0.4 to 4.8 mm, in both layers.

The result is very good, as it was expected, judging from the reading test with the single layer disc. If you compare the two yellow transfer lines with the one we had in the TDR-821 test, you will see that the drive showed a similar good reading behavior in both layers. The drive read the single layer DVD-ROM at 6x CAV.

ABEX TDR-845

The disc is a single sided, dual layer DVD-ROM disc with a capacity of 8.5GB. The only difference between the TDR-845 and the TDR-841 is that the first includes defected areas and fingerprints. The dimensions of the defected areas are ranged from 0.5 to 1.1 mm and the fingerprints are sized from 0.065 to 0.075 mm.

Again the drive easily overcomes the defected areas and successfully finishes the reading test.

ABEX TDV-541

The TDV-541 is a single sided, dual layer DVD-VIDEO disc, with a capacity of 8.5GB. The disc is based upon the TDV-540 series which is designed for inspection and adjustment of DVD-VIDEO players. The discs check the layer switch operation from layer 0 to layer 1 and also include test pictures and test signals for DVD sound files. The current TDV-541 model checks also the error correction capabilities of the drive and includes scratches from 1.8 to 3 mm.

The drive supports 6x CAV average reading speed for the DVD-Video format. The scratched areas did not make the drive slowdown reading and no reading problems occurred. The average reading time was 4.50x.

ABEX TDV-545

The TDV-545 disc is based on the TDV-540 series. It is a single sided, dual layer DVD-VIDEO disc with a capacity of 8.5GB. The TDV-545 includes artificial black dots on the data surface, sized from 0.8 to 1.0 mm. It has also 0.065 - 0.075 mm fingerprints.

Black dots and fingerprints were not a problem for the drive. The test was successful, with a 4.51x average speed.