Photo CDs for storage

[humminboid]

Hello:
I would lilke to store my edited images on photo CDs, and am wondering which brand of archival CD is the best for that. I will need a smaller number for the forseeable future, because I edit remorselessly. I'd say probably 25 will suffice for the foreseeable future, but it seems that the on-line companies only want to sell large amounts, and the information is not very clear to a non-techie guy like me. Soooo...any advice will be greatfully accepted. Do the office supply/computer/ stores sell CDs that are acceptable?

Do CD images degrade over time? I have negs from the late '50s that are as good as when I processed them. Will CDs do as well?

What is the true story about losing resolution when your open a JPEG file? It is all ones and zeroes, so, how does it do that? How to avoid?

I have pictures of a red Corvette that appears very sharp on my monitor, but I send it to Costco for printing, and it is noticeably less sharp, but not unacceptably so.

What could that be all about?

Thank you.

[andyz]

You can Google it for more, but yes, CD and DVD can degrade over time. You're OK for many years with them, but they should be stored in a cool dry environment and in an upright position, is what I've read. If you label them, use a special marker, not a Sharpie. Alcohol(?) in the ink eats through the layers. Also, no sticky labels at all. At least that is what I've read.

I have an on-site DVD, and off-site DVD and two harddrives with my shots.

[Rson]

Cd's are a Dye and subject to fading. The Dye Fades, you lose information.

DVD's are a little different, still the data is not all that safe.

Look into a Magnetic Medium like a Flash drive, Hard Drive or similar.

[kenw]

the short answer is that there are no definite answers to any of these, but short answers aren't always my specialty.....so....

1) archival CDs: buy name brand CDs; Do not use -RW. It is more important to make several copies of each and keep them in separate remote locations. Cool, dark, dry places will work best (Utah would qualify....). Plan to re-copy them in about 10 years onto whatever media is recommended then; just as a plan. The web is full of ridiculous horror stories, most fail to tell you the degradation happened only in theory and only in a boiling swamp. I have lots of 10 year old bargian CDs that are still fine. Now, however, I buy 'name brand" ones at Target, Best Buy, etc.....

CDs will in theory do better than negatives, they are digital, film is analog. Your negatives have been degrading from day 1, you are just fortunate that it hasn't been bad enough to be noticed.

2) If you save a JPG file, reopening it won't hurt it at all, but resaving it can as that's when the additional compression happens. It is why most will recommend that you archive a non-compressed master file such as TIF or RAW. If you do lots of editing on a single image, the best bet is to do your intermediate saves in a TIF or other non-compressed format. That way it won't degrade as it would with each successive JPG save.

3) printing is always the acid test for sharpness, a monitor is a horribly ineffective way to judge sharpness. But then, Costco isn't exactly a gold standard for printing....you might try another shop.

kenw added 0 Minutes and 58 Seconds later...Double Post Merged Below

Originally Posted by Rson

Look into a Magnetic Medium like a Flash drive, Hard Drive or similar.

flash is not magnetic. It is solid state.

[sniperkittie]

If I intended to achive my files, and I do, I would use external Hard Drives. Which is also what I do.

[kneemeaux]

Hello Carl,
Well finally something where I can help a little. You didn't mention how long you were talking about archiving, but here goes.

(1) "Do CD images degrade over time?"

Yes, but not much. Any "RW" format (CD or DVD) is more likely to degrade with time than the "R" formats. Since they are made to be re-writeable RW disks operate using phase-change chemistry and are more affected by temperature. The "R" formats (CD-R. DVD+R, DVD-R) are all write once formats (and strangely enough they really do "burn" when being written) and are less sensitie to temperature. Archival times for a properly stored write-once media are claimed to be in the one hundred year range. Proper storage (as stated above) is cool, dry, vertical, and without the solvents from markers. I'd also recommend multiple copies stored in different locations (far enough apart that fire, flood, etc. won't affect all the copies at the same time).

A far bigger issue with optical formats is compatibility with the drives. Once a given type of media is out of production newer drive aren't tested with it any more and the longer you go the more the chance that a new drive will have trouble reading it.

(2) "I have negs from the late '50s that are as good as when I processed them. Will CDs do as well?"

I don't know what the specs on negs or transparencies are, but I doubt if it's as long as 100 years. The difference is that the file is digital while the negative is analog. If the neg loses some of the information it can still be restored. Once a digital format loses a few bits it may be unrecoverable.

Storage on hard drives is a good idea, but there are risks there too. Just the thermal activity at normal room temperature will cause bit errors given enough time. Copying to another drive after a few years is a good idea both to get a fresh drive and to prevent obsolete formats from haunting you.

Storage on flash drives is also subject to thermal decay, as are any other storage technologies present or future. The sad fact is that there is no storage medium known (short of stone tablets in the Egyptian desert) that has a near permanent life.