Which CD-Rs will last longest?

Q  I have recently transferred all my photos to CD-Rs, with one disc for each topic. How long can I store them like this before transferring them to new discs?

Having seen floppies become unusable over time, how do I ensure that there will always be a medium and method of saving these photos for posterity?
Derek Enfield

A  This is a question that is all but impossible to answer with any confidence because it depends on so many factors, such as the media quality, storage location and atmospheric conditions.

Store a very cheaply manufactured CD-R in direct sunlight, for example, and the disc’s plastic surface may bow or bend in the heat and become unusable within hours.

Conversely, package the discs carefully and store them in an environment with moderate and consistent heating, and minimal illumination, and they could last for many decades – or even centuries.

Indeed, some manufacturers claim their optical disc media have shelf lives of up to 300 years (see these ‘Gold Archive’ CD-Rs on Amazon, for example).

Alternatively – or perhaps additionally – you could consider storing the photos online.

While no-one can say for sure what the future will bring, assuming the world as we know it continues to exist then the online aspect of it is not going away any time soon.

Of course, particular services may come and go but with good stewardship, there’s no reason for any person’s online photo collection should ever become inaccessible – even after they’ve passed away.

In fact, we’ll be exploring the question of what happens to online data after someone’s death in the very next issue, so look out for it. l