In the following tests, we examine the DVD reading capabilities of
the LiteOn SHW-1635S drive with scratched / defective
For the tests we used CDVD Benchmark and Nero CDSpeed. The reference test
- Single Layer media
This is a single sided, single layer DVD-ROM with 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
As we can see from the above graph, the drive managed to read all the way to the end of the test, without any drops in speed, although the max reading speed was not achieved, with the drive reaching only as high as 8X.
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
In this case, the max reading speed achieved was 16X with flawless reading once more. The drive's mechanism did not have any trouble reading both defective areas, producing a smooth speed graph.
- 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.
Both layers were read without any errors and a max reading speed of over 8X.
This test 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 discs is
that the first includes
defective areas and fingerprints. The dimensions of the defective areas ranges
from 0.5 to 1.1 mm and the fingerprints are sized from 65 to 75 micrometers.
Last graph and the most difficult task for the drive's reading mechanism, as each layer contains two defective areas which the drive has to read over. In both layers, the error correction mechanism made quick work of the defects, reaching a max reading speed of 8X and with no errors or speed drops.
The TDV-541 is a single sided, dual layer DVD-VIDEO disc, with a capacity
of 8.5GB. The disc is based on 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.
Job well done with the 541 test media. Max speed reported was 8X and a smooth graph was produced.
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
Same performance as the previous test disc, with perhaps in this case, a much smoother graph. Excellent reading.
All the above tests indicate very good DVD error correction capabilities, even though the max reading speed was not achieved in all cases.