CF or SD card as permanent storage

[Andrea B.]

Is it feasible to use a CF card or an SD card as permanent storage for photo files?

My understanding is that flash memory is degraded by writes, but not by reads. So, with the cost of flash memory becoming ever cheaper, why not make use of CF or SD cards as an additional way to backup and permanently store digital files?

Of course whatever the primary means of storage, backup is always a necessity.

Opinions, links to articles, experiences wanted please!

[Bjørn Rørslett]

Of course this is possible. However, this assumes the media isn't lost in a physical sense. Which, for the diminutive SD card is just a matter of time.

Perhaps making some kind of archival pouch to put them into, with a label of reference attached to it?

[pluton]

A friend once encountered a Sandisk executive at a social gathering.  The Sandisk man said that they are completely confident that information stored on their SD and CF cards will be safe for at least twenty years.
If true, that is better than a spinning hard drive.
And yes, the SD cards are too small and light weight.  I firmly expect to have one blown away by a gust of wind at some point in the future.

[Michael Erlewine]

There are scores of inexpensive pouches available for these cards. I have had the Compact Flash cards go through the washing machine and work just fine. Perhaps as a backup, they would be useful.

M-DISC (Millennial Disc) is a write once optical disc technology available in DVD and Blu-ray forms that they claim will last 1,000 years. They contain 25 GB each. I have started using these.

[elsa hoffmann]

I have seen several CF cards survive a soap and wash. SD I wont trust for 3 minutes

[Anthony]

Nothing electronic is archival.

Have multiple backups and renew them as required.  A lot of care and attention.

Negatives and slides are not archival either, without immense care and attention.

[Bjørn J]

CF-cards may be a good choice for long-term storage, up to around 10 years on quality cards. But like Elsa I don't  trust SD-cards. Actually I loathe them.

[PedroS]

If the principle is the same, why not use SSD to store?

[Hugh_3170]

When travelling, solid state storage is certainly more shock resistant than traditional hard drives that one might have in a small note book, netbook computer, or a digital photo store still fitted with a HDD.   Obviously an SSD is a better choice than a HDD for such devices when used by travellers.

Of course creating multiple copies of images stored in different places is still essential when travelling, so the original SD or CF card as used in the camera can be one of these copies until you  return home. 

[Andrea B.]

There are many choices for permanently storing CF or SD cards. Pelican makes a nice case which could be easily labeled for storage.
Here is a link for one such example: http://www.bhphotovideo.com/c/product/828755-REG/Pelican_0910_015_110_0915_Memory_Card_Case.html
There are other similar choices.

If used for permanent read-only storage, does flash memory need to be occasionally "energized" to prevent bit degradation?

[Frank Fremerey]

In 1996 I wrote a big article on long term bit identical storage for c't magazine. I still consider it as a reference and it is quoted quite often by scientific papers.

The basic idea of long term bit identical storage is to abstract completly from the underlying media. The solution real professionals  (like in BANK as in MONEY) used and use is mirroring the contents over physical remote Data Centers.

Whether the data centers use Tape or Hard Drives or RAM or Flash or apes engraving stone does not matter as long as the underlying technology guarantees bit identical preservation (loss free storage).

So if you are on a decent internet connection, have some Harddrives for local reference and put your important stuff into the cloud (two data centers in geological stable areas on two continents). Of course encrypted with access control and do not loose the keys.

Tres chic is if your files are good enough for a picture bank like Getty or Corbis to take care of storage for you. Thereby you do not only not have to pay for storage but also receive some money back from their sales.

Cheers

Frank (still in the office working on my book)