Tweet
Excellent writting by rdgrimes
.
1) Q: Why should I test my discs?
A: There are no guarantees that your combination of drive, media and software will produce a "good burn" every time. Even if you always use the same media, variations between batches and changes in the brand's supplier can affect the performance of that media. In some cases, even discs from the same spindle have been known to produce widely varying results with identical burn scenarios.
A: There are no guarantees that your combination of drive, media and software will produce a "good burn" every time. Even if you always use the same media, variations between batches and changes in the brand's supplier can affect the performance of that media. In some cases, even discs from the same spindle have been known to produce widely varying results with identical burn scenarios.
2) Q: Do discs wear out?
A: Of course, rough handling, dirt and poor storage techniques will physically damage a disc, and eventually render it unreadable. There is also another type of "wear" that discs go through that is related to temperature, moisture and ultraviolet light. These are the stresses that disc makers often use to test media's ability to withstand aging. If you believe the marketers of media, discs will last for "100 years" and "thousands of uses". The truth is somewhat less definite. One factor that has been demonstrated by many users, is that discs that do not burn well and show higher error-rates tend to degrade much faster. In worst cases, they can fail in as little as a few weeks, but months or years is more likely an accurate prediction for the less reliable of the media that's out there. The media should last for many years with careful storage and use. Remember that all media is "burned" with a laser, heat is the process that makes the dye change characteristics and heat will make it unreadable again. "Re-writable" media is well known for being less stable than "write-once" media. In spite of the seller's claims to the contrary, re-writable discs may have a real-world life of only a few dozen write-erase cycles, or less, before they start to have problems with read-errors
A: Of course, rough handling, dirt and poor storage techniques will physically damage a disc, and eventually render it unreadable. There is also another type of "wear" that discs go through that is related to temperature, moisture and ultraviolet light. These are the stresses that disc makers often use to test media's ability to withstand aging. If you believe the marketers of media, discs will last for "100 years" and "thousands of uses". The truth is somewhat less definite. One factor that has been demonstrated by many users, is that discs that do not burn well and show higher error-rates tend to degrade much faster. In worst cases, they can fail in as little as a few weeks, but months or years is more likely an accurate prediction for the less reliable of the media that's out there. The media should last for many years with careful storage and use. Remember that all media is "burned" with a laser, heat is the process that makes the dye change characteristics and heat will make it unreadable again. "Re-writable" media is well known for being less stable than "write-once" media. In spite of the seller's claims to the contrary, re-writable discs may have a real-world life of only a few dozen write-erase cycles, or less, before they start to have problems with read-errors
3) Q: What's a "good burn"?
A: When a disc responds correctly to the application of heat, the laser creates what is called "pits" and "lands" on the disc. These are what gets read by a drive when you are using the disc. What makes the disc more or less "read-able" is the accuracy in the creation of these, (more precisely the edges of them). If the media cannot properly respond to the laser, or if the laser is not properly calibrated, the edges become blurred or jagged, and reading becomes more difficult. A "good burn" results in a disc that can be read by a wide variety of drives at varying speeds. A marginal burn results in a disc that can be read by only some drives (the "better readers"). A marginal burn may also result in a disc that can be read, but will have many read-errors that cause slow reading problems and even corrupted data. Of course, a bad burn results in a "coaster" that no drives, or very few drives, can read.
A: When a disc responds correctly to the application of heat, the laser creates what is called "pits" and "lands" on the disc. These are what gets read by a drive when you are using the disc. What makes the disc more or less "read-able" is the accuracy in the creation of these, (more precisely the edges of them). If the media cannot properly respond to the laser, or if the laser is not properly calibrated, the edges become blurred or jagged, and reading becomes more difficult. A "good burn" results in a disc that can be read by a wide variety of drives at varying speeds. A marginal burn results in a disc that can be read by only some drives (the "better readers"). A marginal burn may also result in a disc that can be read, but will have many read-errors that cause slow reading problems and even corrupted data. Of course, a bad burn results in a "coaster" that no drives, or very few drives, can read.