osta cd-r compatibility study results from phase 2 - OSTA - Optical ...

CD-R Compatibility Study – Phase 2
the older 1X recorders tended to write discs at considerably higher powers than were
ultimately mandated by the Orange Book. Furthermore, these writers lacked the active
write power control that was recommended in the final specification. This often showed
up as excessively high values of symmetry (or beta) reported by CD testers. Some of the
original CD-R media offerings were tolerant of this overpowering and, in fact, required it
for best results. Newer Orange Book Part II (version 2.0) compliant media were designed
to function optimally in the strict, designated write power range and encountered
understandable performance degradation when written in overpowered, non-standard
conditions. All newer writers, including 2X, 4X, and 6X offerings, have sophisticated
write power selection and control capabilities and generate considerably higher quality
discs than do the older 1X devices. This result has been extensively corroborated by a
number of other comprehensive studies.
When the Orange Book was finalized, most, if not all, of the original manufacturers of
non-standard writers modified their devices to conform to the final requirements.
However, there still is a remnant installed population, albeit minuscule, of the older, nonstandard
writers in use. Some of these can be upgraded to be in compliance with the
Orange Book (usually by the manufacturer for a moderate price) but this information is
not always widely publicized or known. It is quite possible that no problems are
encountered when reading with these devices, but when using newer, multi-speed capable
media types, users may encounter what appear to be “compatibility” problems due to the
violation of Orange Book writing guidelines.
The current release of the Orange Book (Part II: CD-R, Version 3.0, December 1997)
continues to refine the relationship between CD-R media and CD recorder writing
functions. The defined recording speeds now include 1X, 2X and 4X nominal CD speed.
Improved definitions have been established for CD-R media to implement optimum
writing power controls between the recorder and the media. Likewise special information
can be coded into blank CD-R media to identify its disc type and the starting or indicative
optimum writing power.
Future improvements to CD-R media and recording systems can be expected due to the
ongoing work of Philips and Sony as they further refine Orange Book specifications.
Likewise the Orange Forum (formerly known as OSJ, the Orange Book Study Group of
Japan) continues its work to support Philips and Sony by addressing CD-R market
introduction issues.
Today, concerns regarding compatibility are greatly diminished due to major advances in
the quality and robustness of writers, media, and readers. Like all recordable technologies,
some problems are still encountered with CD-R. However, in almost all instances, these
can be attributed to systems conflicts, software deficiencies, or the occasional
malfunctioning writer or reader.
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