Photo CD Life

[Rockslinger]

Apologies if these questions have been previously asked and answered.

What is the useful life of a photo CD (in particular the Kodak photo CD)?

Also, what is the useful life of a home created DVD, Mini DV and VHS tape? My experience with home created VHS tapes is that they last about 10 years and then the quality degrades rapidly.

 

[Anynym]

Someone will no doubt link to a recent thread in which some folks made certain claims about different quality of CD or DVD media, and the abilities of various burners. (Personally, I don't believe there's any measurable difference, except perhaps in the quality of some of the dyes, as discussed in some of the links cited below.)

But there are various factors which will affect the life of a photo CD, including the quality of the dye (the layer which is "burned"), the storage environment (cool should be better than hot, dark better than bright, scratches are evil, etc), and the data being stored.

CDs are generally written with some Error Correcting Codes, which can adjust for certain bit errors, but which can also render tracks unreadable if too many errors are present. Photos tend to be tolerant to bit errors, as long as the track is readable ... so perhaps making another copy every few (10?) years wouldn't be a bad idea.
http://www.cdrfaq.org/faq02.html
http://www.cdrfaq.org/faq07.html#S7-5
http://www.mscience.com/faq53.html

 

[frankcastle]

ARen't gold CDs supposed to have a longer shelf life? I think they're called archival disks?

 

[Papi Chulo]

https://terb.cc/vbulletin/showthread.php?t=125988

 

[Anynym]

Someone will no doubt link to a recent thread ...

Told ya! (And, thanks fo Papi for providing the link.) And isn't it always nice to see someone anecdotally confirming what I said, and what is confirmed by the experts in the links? So somewhere between a couple weeks, and a hundred years, the discs might well fail. Doesn't that give you a warm fuzzy feeling?

I'd make a fresh copy every decade or so, and keep the copies in a nice, cool, dark environment. But maybe that's just me.

 

[Rockslinger]

Thanks guys.

Sounds like we are still in the "trial and error" stage. The major concern is that some photos are irreplaceble such as baby and grandparent pics.

I was told that there are two ways to be safe:

1) Produce hard prints from the CD. Back to the old way of prints.

2) Store the images on the actual memory card.

A friend told me that weird things happen to hard drives so they might not be that safe an alternative.

 

[Anynym]

Prints can fade, and can be damaged by water.

The "actual" memory card can lose bits and render the contents unreadable.

You can pay companies to keep copies for you, and they might keep a couple copies on hard disk (e.g. using a redundant or mirrored disk array such as RAID-1), guarding against Hard Drive failures. They might occasionally pull out a hard drive, and set it aside in case the computer fails (and they can simply re-insert that drive into a new machine - the drive doesn't age as much just sitting around, although it could eventually refuse to start spinning at speed). Occasionally, such a company might back up the disks to tape (e.g. a full backup every month, complementing a daily or weekly incremental backup). Or a backup may be sent to "other" Network Attached Storage or other backup devices. And/or to DVDs, etc.

For personal use, CDs and DVDs would normally be expected to last several years. (Sure, some have been found to only last a few weeks, but that's not the norm.) Keep a couple copies, under "appropriate" environmental conditions, and in as many different formats (printed copy, CD, DVD, etc) as you feel comfortable with. Every several years, refresh your collection with at least a couple new copies (and test the copies as they're made).