Because degradation of the data layer will render the disc useless well before the polycarbonate begins to deteriorate, the relative degradation rate for the polycarbonate layer is not used for life expectancy considerations. Physical mishandling of the disc is usually the cause of polycarbonate layer damage. The polycarbonate may also flex or bend if stored for a long period of time in a nonvertical position.
So what is the life expectancy of a disc? First, we must define life expectancy. For most users, it means the length of time for which the disc remains usable. But that implies some acceptable amount of degradation. How much and what type of degradation is acceptable? With CDs and DVDs, the user does not notice early degradation because the error detection and correction capability built into the system corrects a certain number of errors.
The user notices a problem only when the error correction coding is unable to fully correct the errors. One method for determining end of life for a disc is based on the number of errors on a disc before the error correction occurs. The chance of disc failure increases with the number of errors, but it is impossible to define the number of errors in a disc that will absolutely cause a performance problem minor or catastrophic because it depends on the number of errors left, after error correction, and their distribution within the data.
Manufacturers tend to use this premise to estimate media longevity. They test discs by using accelerated aging methodologies with controlled extreme temperature and humidity influences over a relatively short period of time.
Expectations vary from 20 to years for these discs. Few, if any, life expectancy reports for these discs have been published by independent laboratories. This testing for R discs is in the preliminary stages, and much more needs to be done. ROMs are generally mass-produced and contain music, video, computer applications, or interactive games. ROM disc longevity is determined by the extent to which its aluminum layer is exposed to oxygen.
Oxygen, including pollutants, can migrate through the polycarbonate layer or the hard lacquer layer CD label side and edge , carried in by moisture. Oxygen or moisture can more easily penetrate through scratches, cracks, or delaminated areas in the label. Yes the can, there are done several test that show this. Things like sunlight etc. I am sure this is quite save. Reply Reply with quote Reply to thread Complain. Burn some and read them in another system. As you said, they aren't for archiving.
Chris -- A picture is but words to the eyes. They're no more likely to fail than used CD-R's. Two ways a CD-R will fail. I do not need them for archiving just to burn some photos for friends and families Thanks for input. Hi Halpren, just a simple question and a few simple answers do not clutter up this forum. We dont need the OT stuff too when there are already hundreds of forums already out there that discuss the topic in question jsonic wrote: Hi Halpren, just a simple question and a few simple answers do not clutter up this forum.
I am just need to start using them haha thanks for ur input everyone -- hide signature I think you "clutter" the world. Can you do something about it? So far my list on things that you don't know but pretend you know are: Cameras Photography Marketing strategies Technology in general Flashes Computers Netiquette in forums and lately off-road vehicles Maybe the new F or was F? Andy Williams's gear list: Andy Williams's gear list. Or maybe check for air-bubbles between the silvery coating and the plastic.
Rot takes time and eats away your disc slowly, so there is always time for salvage. Sparky, Was that your Belkin router or your Black and Decker router? F Forum M My threads. You may also like. Sony ZV-1 review. Will vlogging change your next camera? Latest sample galleries. Tamron mm F2. Panasonic S 35mm F1. DJI Mavic 3 Cine sample gallery. Nikon Z9 pre-production sample gallery. See more galleries ». Latest in-depth reviews.
Read more reviews ». Latest buying guides. Best video cameras for photographers in Best cameras for Instagram in Best drones in Best cameras for vlogging in Check out more buying guides ». Nikon Z9 initial review. Sony a7 IV initial review. Nikon Nikkor Z mm F2. Sigma mm F Discover more challenges ». Five percent of participants had issues with the old discs. The association did not investigate the individual complications — so some could be software related.
The backup discs you make today may become damaged or obsolete in the future. CDs and DVDs can be part of your backup plan, it says. They are, after all, inexpensive, compact, and portable. Especially when it comes to digital photos, the Library of Congress suggests a three-pronged approach: save them to discs or USB flash drives, upload them to online storage sites such as Flickr.
Then, when CD-Rs, flash drives, or websites become outdated, move everything to their replacements. That may be plenty of time, considering the speed of overturning technology. CDs may feel like 8-tracks in five years. Where can you get 4G? And what is 2. Already a subscriber? Monitor journalism changes lives because we open that too-small box that most people think they live in.
We believe news can and should expand a sense of identity and possibility beyond narrow conventional expectations. Your subscription to The Christian Science Monitor has expired. You can renew your subscription or continue to use the site without a subscription. If you have questions about your account, please contact customer service or call us at
0コメント