There is more to it than meets the eye. That is clearly the case with shopping for blank new DVD discs.
The Consumer Council has released the results of a test that promises to help solve consumer disappointment that a seemingly flawless DVD may neither record nor read stored data.
First and foremost, consumers are advised to examine carefully the DVD discs for any scratch or dust on the surface as that may well render them unable to record or be read properly. This is due to their precise high data density structure.
Or, better yet, look for DVD discs that come with scratchproof feature. The test has shown that scratchproof samples were in good robustness condition after scratching whereas those without this feature were all found to be out of order.
After the visual inspection, consumers should then carefully assess the reliability of the DVD discs in relation to their read-and-write function and, equally important, compatibility with DVD players and recorders (both existing in use and others that are likely to be used).
According to the test, all samples fared well in the performance of both the read-and-write function and recording speed.
But, after recording, the quality of some DVD disc samples was found to deteriorate rapidly to a level so much so that it may trigger a higher possibility of error reading.
The majority (85%) of the test samples displayed good compatibility with DVD players and recorders. Factors that contributed to the effect of read-and-write function include: different recording systems, DVD discs, DVD players and software used for recording.
It is believed by experts that only 10% of the incompatibilities are caused by DVD discs and, in most cases, an update of the DVD-recorder-firmware could solve the problem.
Consumers preferring CD discs should take note that there are three types of CD discs, namely, the read only CD-ROM discs, the 1-time recordable CD-R discs and the multi-rewritable CD-RW discs. Manufacturers have claimed that the number of the rewritable can reach almost 1,000 times for the CD-RW discs.
It is difficult to estimate with any accuracy the lifetime of DVD or CD discs as they are relatively new products in the market.
Experts have opined that discs with higher robustness will usually have a higher degree of reliability and might get a longer lifetime, but robustness cannot be taken as the only factor in this aspect.
A word of caution: as information technology is ever changing at a fast pace, consumers who want to keep data for long period of time will do well to adopt measures to ensure the discs could still be in function in years ahead.
Make two disc copies, check them regularly to ensure their reading-devices are running, store them in different clean, dry, cool and dark places. And for every two years, copy the data back to hard disk and rewrite again. If a new technology emerges, produce additional copies.
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