Since I seem to be one of the few people around who haven't lost any data from CDs and DVDs in the 9 years or so I've been recording data, it's a pity I can't offer any advice regarding choice of brands.
In the beginning I used Kodak Gold with Infoguard. I used to buy them in boxes of 30, each in their own jewelcase nicely wrapped in cellophane. I then progressed to buying spindles of 50 and 100 of all sorts of brands. Over the years I accumulated a pile of well over 100 failed recordings of both CD and DVD.
It's clear that a certain percentage of discs have damaged surfaces. It's therefore critical that data be verified before the disc is stored in your archives.
The problem is, that the burning process itself takes such a long time it's easy to skip the verfication process. This in my view is the cause of most later discoveries of failure. When some people discover, say 5 years down the track, that their DVD reader/burner can't read certain files, are such people absolutely certain that such files were ever readable?
Now I say I haven't lost any data from optical media, but that statement needs qualification. I haven't lost any data that I know was initially recorded properly, but I did lose some data once by failing to observe my own common-sense practice of immediately verifying the data before storing the disc.
It was my practice to transfer files to CD and DVD to create some space on an almost full hard drive before deframenting it. On one occasion, I was in a hurry packing for a trip, burned about a dozen CDs and DVDs without verifying or labelling them. Deleted the folders and defragmented the HD. When I returned to my studio about a week later, I set about labelling the small stack of burned discs and to do this I had to read what was on them.
One of the discs, a Ritek CD-R, had problems. It contained about 100 D60 RAW images, but the last 20 or so were unreadable. I did my best to recover the data using free programs downloadable from the net and succeeding in recovering 2 or 3 of the damaged files.
The reason I mention this is because, had I not been in such a hurry, I might have labelled that particular CD at the time it was burned and stored it away. 5 years later (and it was recorded 5-6 years ago) I might have tried to access the images for the first time and discovering that 20 or so were not readable, would now be complaining on Luminous Landscape that optical media is not reliable.
Just as a matter of interest, after reading this thread, I retrieved that particular faulty CD from its wallet to see if the good images were still readable. They are. Despite the fact the disc was faulty at the time of recording, it appears to be no more faulty 5 1/2 years later.
I downloaded a program called IsoBuster which claims to recover data from all types of optical media, including Blu-ray discs, and found that all the damaged files on this disc can be recovered if I instruct the program to ignore all errors. The number of errors range from 1 to about 20 but unfortunately the RAW files still cannot be opened in ACR. I get a message, "Not the right type of file".
There are one or two free programs that claim to repair Canon RAW files but I can't seem to get them to work.
Nero burning software has a utility feature that analyzes disc performance and scans its surface for damage. Green indicates the areas where the surface is good; yellow where there's damage and red where bad. Out of curiosity, I checked this faulty disc and sure enough, there were large areas of yellow. The disc next to it in the same wallet, recorded about the same time and from the same spindle, has a perfect surface, all green and no errors.
