so roughly 5 years ago, I decided to attempt to debunk the whole "sharpie's are bad for CD-Rs" thing. I took a Prodisc shiny silver surface CD-R, and burned it. Then I scanned it. Then I put 2 thick rings of sharpie marking along the inner and outer edges of the laquer, and scanned it again. Then I scanned the disc periodically over several weeks, then months. I kept the disc, and ignored it for a while. Now I've taken it out of "retirment" and scanned it again.
My original goal, was to compare time lapsed scans of the disc to the very first few, and see if the beginning and ending of the disc exhibited increased error levels, when compared to the middle of the disc.
Sadly, it appears I have lost all my original scans!
However, judging from the scans I'm seeing now, the disc chosen may have been a bad choice. The Prodisc CD-R has now degraded into such utter crap, that it's possible that if the were error rates increasing in a small amount on the inner and outer edges, I would not be able to tell!
An interesting thing I noticed was that I've received some conflicting scan data from several different drives though. The PX-712a reports very high errors at the beginning of the disc, up to about 1/3rd, which is beyond where I put sharpie markings, and the outer edge is fine. There are also C2 errors spotting all the way along the disc.
My LiteON 48125W has a HECK of a time with the disc, and shows thousands and thousands of errors according to Nero CD/DVD Speed... I'll re-test with K-Probe when I get a chance, but the results should be about the same.
Once I get my Plextor Premium drive installed again, I'll retest with that, and see what comes up again, and I'll post the scan as well at that time. Right now I'm just in the middle of a nasty system re-install, and all my logins and memberships with webspace servers have to be re-setup
So in conclusion.... I can't see any changes that might have happened because of the sharpie, but I can say with great certainty that if there *IS* quality issues caused by the shapie markings, then they were far FAR less significant then the degidation level brought about by time on the Prodisc CD-R.
For reference sake, the CD-R was kept in a CD Jewel Case, in a room temperature enviroment (my room
), kept out of direct sunlight, and usually any light at all. The CD-R was handled with extreme care, and there are no visible scratches on the disc, on either top or bottom. Also, I have not noticed any colour bleeding from the sharpie marks, or anything else that might indicate degridation, or cause for degridation of quality.
As a final note, I'm really REALLY happy I don't use Prodisc media for ANY personal stuff
Punch Cards -> Paper Tape -> Tape Drive -> 8" Floppy Diskette -> 5 1/4" Floppy Diskette -> 3 1/2" "Flippy" Diskette -> CD-R -> DVD±R -> BD-R
The Progression of Computer Media