Re: [APML] O.T.: batch conversion of Tiff to JPG

[Jerry Lodriguss <jerryapml@astropix.com>]

Hi Michael,

There has been a ton of publicity about the longevity of CDs and DVDs, 
based on one anecdotal story that the media has picked up and it's been run 
everywhere because it was distributed by the AP: 
http://www.wired.com/news/technology/0,1282,63355,00.html

How much truth is there in it?  Probably a little bit, but being the media, 
it's probably overblown.

The original promise of CDs was a lifespan of 100 years,and that's what 
they have tested at IFF they are stored correctly.  That hardly matters 
though because even if your media lasts that long, you won't find a 
hardware reader a century from now. It's like finding an 8-track tape in 
the closet. Or even a 5 inch floppy.

Whatever the life span of a CD or DVD, there are some things you should 
definitely be doing:

Keep multiple backups in different physical locations (preferably written 
on disks by different manufacturers)

Store them in individual tyvek sleeves or original acrylic jewel cases.

Keep them in a cool, dry location away from sunlight.

Do NOT write on them with ball point pens.

Use only water-based markers, others may contain solvents (if it says 
"non-toxic" it's probably water based.

Don't use labels.

Don't flex or bend them when you take them off the jewel case spindle. 
Remove it by pressing your thumb and third finger on edges near the top and 
bottom of the case and pressing on the plastic clasp in the center with the 
other hand.

Always handle by the edges only.


A very important thing to know about CDs is that the layer that contains 
the data is actually on the top of the CD, and not the bottom. The bottom 
is a transparent plastic that the laser reads the data through. The actual 
data is just below the label side, which is the side you would write on.

Good info on CD storage here: 
http://www.aallnet.org/sis/tssis/tsll/22-04/presrv.htm


Some good info on the entire topic here:

http://www.dpconline.org/graphics/events/digitallongevity.html


The CD guys can say film is dead all they want, but in 100 years you will 
still be able to access the data on a Kodachrome slide shot today by simply 
holding it up to the light and looking at it with your eyeball. With 
digital data, you, or your descendants, are going to have to translate to 
the latest-greatest storage media, every ten years.


Jerry



>My main reason for making a secondary mildly compressed back-up on DVD was
>my concern regarding the longevity of these disks.  I have heard that the
>dye in them can fade with time making the disk unreadable.  When I archived
>my 70 GB of data that was on a whole draw filled with CD's, I noted that 4
>of them had defective data.  Fortunately these were also on my hard drive so
>I did not loose any files.  Any comments on the longevity of DVD's or
>alternate ways to back-up would be appreciated.

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