CDs vs. DVDs for data archiving

[how786]

I'd read this thread: http://palimpsest.stanford.edu/byform....70.html

I'm about to undertake a project that involves archiving old negatives and slides.
I'm scanning with a Nikon 9000 scanner.

Should I be using DVDs or CDs for storage?

Thanks
Dr. Howard Posner

[johns0]

I you got up to 700 mb of files use a 80 minute cdr,if you got 4.37 gb of files use dvdr,simple as that.Link is dead?

[porphyra]

Tis true. If you have relatively little, then archive using CD-R. If you would need archival in the gigs then go with DVD-R/+R.

What however is important, is quality media, whether for CD or DVD. If you are archiving, then make it a priority to seek out and buy top quality media.

BTW > Taiyo Yuden makes excellent media, for both CD and DVD. Maxell is excellent too (DVD-R and some CD-R's).

[johns0]

Also after you burn do a thorough check on the cd/dvr to make sure the data was burned ok.

[holistic]

DON'T USE DVD MEDIA .. I mean really just look at the number of posts on this forum for people backing up 'their' precious DVD's. It is obviously an inferior product. :P

Joking aside , the volume of data will dictate your best media needs.

As a reference : Using Photoshops *.psd (non lossy format) with say 10Mb per file sizes you have storage for 70 photos. If however you choose to store in a lossy format such as JPEG you can store possibly 10 times that amount (depending on compression).

[how786]

Wow! Thanks for all the replies guys! I really appreciate them.
OK.....many of my 6X7 scans are over 200 meg each which is why I thought of DVDs rather than CDs. My 35 mm scans are 68 meg.
(scanning at 4000 DPI)
Until now we've been using 63 minutes mitsui Gold CDs, then 74 minute Mitsui Gold CDs after they stopped making the shorter CDs.
Why?
The longer CDs have significantly more errors, things like BLER etc.
(We have some pretty sophisticated error checking devices.)
The highest speed we can record at with very low errror is 16X. Any faster, and the errors skyrocket.
Concerning DVDs, how does their longevity compare to Gold CDs? My understanding is that there are no Gold DVDs. Also, how does the error rate compare?
If you think all these are favorable, what recorder/media would you recommend?
Thanks!
Howard

[8trackkid]

In my humble opinion...
USE BOTH
As CD-R media is both cheap and very quick to burn, why take the chance that one method will fail with something that is so irreplaceable?
Some DVD-R media is especially prone to failure and errors when burning data, due to uneven dye spread, cheap plastic defects, etc. Most stand alone players are more forgiving of such errors on DVD-R for video, while image files read on your computer's dvd-rom drive may not be so forgiving. Excellent quality CD-R media is only a few cents a disk on sale, and the manufacturing technology is more stable than that of DVD-R.
Hope this helps...

[porphyra]

If you are that picky about errors then i think DVD-RAM or a Tape drive are your best bets. DVD-Ram has an Error checking mechanism as you write, so each sector is verified as it is written (or something to that effect, dont start flaming me here).

I dont think there is an answer to your question, as it simply does not exist. There are no long-term studies on life, stability, accuracy etc. for either of them, and thus all you will get are educated guesses (in most cases :P ).

I would certainly go with a cartridge type DVD-RAM. The cartridge prevents exposure to dust and moisture. These last quite long and are preferred to back-ups at the consumer level. There are more sophisticated devices avaliable at the professional level, but you are looking at big $$$ where data integrity is crucial.

[TBoneit]

One other thing to keep in mind is that dvds are somewhat harder to damage because the data is in the center of the disk rather than on top as in CD-roms.

Take a junk disk and use a ball pint pen and press a littl on it as you write, you'll see the dent in the data surface, then do the same to a junk dvd and you'll see what I mean

On the other hand it is easier to trash a CD you want to get rid of safely... just scrape off the data.

Cheers

[tatty]

The fact is that you already have the most reliable and durable storage medium known - the photo negative ! In terms of reliability and mtbf there's nothing even close. Monochrome negatives in particular, properly stored, will last for centuries, possibly millennia, whereas you'd be hard pushed to get any CD manufacture to guarantee five years. That's progress for you!

Digital storage may sound like the answer to a maiden's prayer but it is a two-edged sword. While it offers great quality, fabulous storage capacity and loss-less copying, it relies totally on cutting edge technology, and compared to analog - or even chemical - technology it is as reliable as a chocolate tea-pot. We have to use it but also have to pay the price, and that is never-ending vigilance.

All you can do is use the best (i.e. lowest error rate)that fits your file sizes and is available now, whether it be CD or DVD. The media used will change over time anyway. To ensure quality you will have to monitor and re-master the disks on a regular basis as technology moves on. You will, of course, keep the negatives in the deepest, safest vault in the universe. They will always be the ultimate backup. Everything else is a working copy.

Good luck !

[how786]

Dear Tatty,

Thanks for the reply.
What you say is true for B&W negs and, perhaps, for Kodachrome. Kodachromes should last 50 years or so but mot hundreds.
Color negative films or for most other 'chomes are not archival. We already have seen pretty significant color shifts and fading in all color negative films (30 years old), Ektachrome, Agfa(crap)chrome etc.

Best
Howard

[SteelSpy]

Not that this is important to the discussion. Just thought of it when I read the thread.

What you say is true for B&W negs and, perhaps, for Kodachrome. Kodachromes should last 50 years or so but mot hundreds.

When we cleared out my grandparents house, I found a Brownie Hawkeye camera. Still had film in it. So just for giggles, I had it developed.
Every last picture on the roll came out perfect. That film had been in the camera for over 40 years. B&W rocks!

[how786]

You were VERY, very lucky.
I've seen background radiation fog UNdeveloped B&W film after about 10 years.

Howard

[disturbed1]

I'd personally use DVD-RAM and Mitsui medical grade CD-Rs. Most of the DVD Media available isn't suitable for long term critical storage needs. It may and it may not last. DVD-RAM in the carts would be the way to go.


Even with the high grade ($$$) blank DVDs, there just isn't enough tests, nor information out there to give it a thumbs up to use for this type of work.

CD-Rs have been around for a while, and the technology has greatly improved. The cheap grade CD-Rs are higher quality than the high grade DVD blanks (in general).