DVD Error Correction
In the following tests, we examined the DVD reading capabilities of the drive (error correction) with scratched / defective DVD media. For the tests, we used CDVD Benchmark and Nero CDSpeed. The reference test media comes from ALMEDIO.
- Single Layer media
This is a single sided, single layer DVD-ROM with a 4.7GB capacity, and its surface has an artificial scratch of dimensions varying from 0.4 to 3.0 mm.
The following transfer rate picture comes from the CDVD Benchmark v1.21 transfer rate test.
A goog read without any problems with the scratched DVD-ROM disc.
This is also a single sided, single layer DVD-ROM of 4.7GB capacity. The data structure of the disc is exactly the same as that of the TDR-821, with the difference that there are no scratches on it but instead, defective areas of dimensions ranging from 0.5 to 1.1 mm. There are also fingerprints sized between 65 and 75 micrometers.
The god performance continues with the second DVD-ROM.
- Dual Layer media
This is an 8.5GB dual layer, single sided DVD-ROM disc with artificial scratches of dimensions ranging from 0.4 to 3.0mm, on both layers.
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 defective areas and fingerprints.
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 disc checks the layer switch operation from layer 0 to layer 1 and also includes test pictures and test signals for DVD sound files..
The current TDV-541 also checks the error correcting capabilities of the drive and includes scratches from 0.4 to 3.0 mm.
There is a serious issue here, since the drive had hard times to read the second layer of the disc. Although the test did not return a read error and reading resumed as the scratch became narrower towards the inner part of the disc (OTP), the behavior is not the expected.
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 0.4 to 1.0 mm. It also has 65 - 75 micrometer fingerprints.
These kind of defects were easily overcomed by the drive, giving a very smooth reading graph.