Labeling discs with markers and how it affects burn quality scans

vbimport

#1

Has anyone done any testing on how disc labeling affects the burn quality of a disc and the resulting scan? I’ve been using a Sharpie Ultra Fine Point marker to label discs for years and figured it was “safe” to use…

However, I recently bought a spindle of branded Verbatim AZO 16x DVD+R (MCC 004 Made in Taiwan) to use in an attempted comprehensive quality burn-off. I examined the bottom of each Verbatim discs for scratched or debris prior to burning and labeled it with the burner used, burn speed, and disc number with the aforementioned Sharpie on the top of disc. I would then burn and scan the disc. I created test discs at every burn speed of my AD-7260S (4x, 6x, 8x, 12x, 16x, 18x, 20x) and got results that were inconclusive and somewhat random. Moving up in speed didn’t necessarily correlate to more errors or a worse burn. So, I burned a second set of test discs at every burn speed and got very little consistency to the results of the first set of burns. Some burn speeds were better in the second set while others were worse. I was puzzled by the results and decided to burn a 3rd set of test discs but this time labeled the discs in the small clear center hub area (not on top of the burned surface). To my surprise the disc scans were better than before in PIF failure count and more consistent as burn speed increased.

Either these discs are horribly inconsistent or writing on them with the Ultra Fine Point Sharpie appears to damage them. I plan to do additional testing by scanning discs before and after they’re written on to further narrow in on this as well as burning and scanning more discs without writing on them to see if I can achieve some sort of consistency between multiple burns of the same speed.


#2

I’ve never labeled then burned because I heard back in the first CD Burner days that this might create a potential imbalance.

In the past few years, I’ve heard more about the chemistry of Sharpie types versus the Disk Blank’s chemistry.

I’ll be interested to see other comments.


#3

Here’s an older thread that discusses it from a more general, informal standpoint: http://club.myce.com/f33/okay-write-discs-marker-160228/


#4

[QUOTE=Albert;2695993]Here’s an older thread that discusses it from a more general, informal standpoint: http://club.myce.com/f33/okay-write-discs-marker-160228/[/QUOTE]That thread basically says a sharpie is benign. That’s the assumption I’ve been working from for years.

However, I’m definitely seeing something. I need to confirm if the issue is related to labeling or just labeling before burning or what. More discs will be sacrificed for the cause when I get home from work.


#5

Curious: what drive are you using for scanning, and at what speed? What’s the testing protocol: back-to-back burns + back-to-back scans, or are you taking a break between each burn and between each scan?


#6

[QUOTE=Albert;2696016]Curious: what drive are you using for scanning, and at what speed? What’s the testing protocol: back-to-back burns + back-to-back scans, or are you taking a break between each burn and between each scan?[/QUOTE]I’ve been scanning at 8x using Nero CD/DVD Speed with my Lite-On iHBS112. Burns and scans have been pretty much back to back. Burn with the AD-7260S and scan with the iHBS112. When both are done save the data, put the scanned disc in a case, move the burned disc to the scanner, load another blank to the burner, start the scan, and start the burn. Rinse and repeat.

Frankly the whole thing is puzzling to me since the reflective layer being burned is in between a polycarbonate sandwich with DVDs, and isn’t like a CD-R where it was on the top side of the polycarbonate with a thin lacquer or coating over it. It seems hard to believe that the pressure from writing on the disc can damage the reflective layer.


#7

I had smirked at the notion that some Sharpie ink would cause out-of-whack spins but, in the last year, I had a completely different experience with several Pioneer DVR 118s.

Somehow, they allowed a mis-aligned DVD to start spinning at ‘full speed’ and those exploded in the drives. Hundreds of shards and pieces, flakes, everything.

You’ve seen a DVD that’s been snapped in two. Maybe in 4 or 5 pieces. Maybe you’ve seen one smashed on the street. But they were nothing like these 118s’ obliteration.

I mean hundreds of tiny flecks and shards, pin-sized spikes, all thru the unit. There’s be a ‘sheet’ of some material that might be fingernail sized, but everything else was closer to sand-pellets.

When it happened on one, I just wrote it off as a queer unit. On the second one, I was thinking, “Did I do something wrong? I’ve loaded tens of thousands of disks, but NOW I don’t know how?!!” When the third unit blew up a disk, well, that was it. Three out of 10 or 20, whatever that order was. We started pulling them out and ‘saving’ them in a dust-collector corner.

The strange notion was the incredible RPMs that disks must attain. How else could those pieces be so thoroughly obliterated? I mean, porcelain blades on a power-saw don’t shatter in so many pieces!

With that in mind, maybe in fact a TINY shred of Sharpie ink would create some off-balance during that high speed spinning. (Of course, probably McLaren engines would, too. REDLINE!! REDLINE!!! I can hear Cholla muttering, “She ain’t learning to double-clutch on MY rigs!”)


#8

I am planning to draw some radial lines on a disc (symmetrically) as one of my tests. That should prevent an imbalance and reduce the variables to some sort of reflectivity change or pressure damaging the substrate.

I also plan to test with some printable 16x Verbatim DVD+Rs.


#9

Its not inconceivable that your variable scans are simply the result of normal variation between discs and burns. For statistical accuracy, I’d suggest using ONLY one burn speed and simply comparing the disc scan before and after its marked on. You can do an identical set of scans with marking before the burn. But again, variation is normal. More than anything, what your posted results show is that you have some pretty good 8x media, and that’s the burn speed to use for testing.


#10

[QUOTE=CDan;2696027]Its not inconceivable that your variable scans are simply the result of normal variation between discs and burns. For statistical accuracy, I’d suggest using ONLY one burn speed and simply comparing the disc scan before and after its marked on. You can do an identical set of scans with marking before the burn. But again, variation is normal. More than anything, what your posted results show is that you have some pretty good 8x media, and that’s the burn speed to use for testing.[/QUOTE]I was already thinking along the same lines myself. Burn at least 10 discs with the identical settings and see how much variation there is in the media/burn and if marking it after scanning the first time changes anything. That would be another valuable data point.


#11

I think the radial lines provides a good statistical test, but I’d argue against its real world validity. “How many disc labels would I create using 1 or 2 completely balanced single lines?” Three guesses…

So whatever answer this testbed provides, I don’t think it has a real world use. That said, what kind of Balancing Design could do this?

A checkerboard pattern? A pie-slice / wagon-wheel with 2 alternating colors -or rather, one color, one ‘blank’? That might be the interesting Real World comparison because The Weight Of Ink would be located on certain sectors and absent from others. Hmmm…

And I’m still wondering, “Why bother pre-printing on a disk-to-burn? Why not scrawl a note, shove it and a successfully burned disk in a sleeve, and set it in front of the printer to complete the print job?” I’m trying to think of the benefits (any?) vs the risks (imbalanced burns?).

There’s something else to consider. Disk Players have handled Printed Disks ‘forever’. None of them have a history of blowing up or refusing to play because of ink-imbalances, right?

But - burning is considered to be a far more delicate and precise operation than playing. Yes? No?


#12

[QUOTE=ChristineBCW;2696046]I think the radial lines provides a good statistical test, but I’d argue against its real world validity. “How many disc labels would I create using 1 or 2 completely balanced single lines?” Three guesses…

So whatever answer this testbed provides, I don’t think it has a real world use. That said, what kind of Balancing Design could do this?[/quote]It would perhaps illustrate if it is a balancing issue or not. Personally, I’m quite skeptical that it’s a balance issue. The weight of the ink has to be so statistically insignificant…

And I’m still wondering, “Why bother pre-printing on a disk-to-burn? Why not scrawl a note, shove it and a successfully burned disk in a sleeve, and set it in front of the printer to complete the print job?” I’m trying to think of the benefits (any?) vs the risks (imbalanced burns?).
Well, assuming my theory pans out, who would guess that labeling a disc prior to burning it will affect the burn quality? Obviously it’s not a big deal to just label it after.

But - burning is considered to be a far more delicate and precise operation than playing. Yes? No?
I’m not sure it’s more delicate, but you obviously only get one chance to get it right so it is more critical.


#13

There might just be something to the imbalance theory. A disc with a pretty symmetrical radial pattern burned and scanned well with only 237 total PI failures. One that had a radial pattern contained in only one quadrant of the disc has significantly more PI Failures (1540 total). 5 discs burned at the same speed (8x) with nothing written or drawn on them scanned between ~200 and ~700 total PI Failures. Labeling those discs after they were burned and scanned did not change the number of PI Failures on a subsequent scan.

Maybe it’s all a fluke, but a trend seems to be developing.


#14

Its also true that no 2 discs have identical balance from the start. Tolerances exist on balance and on centering of the hole, as well as the size of the hole, all of which effect scans.


#15

Well, I continued burning unlabeled 8x test discs this morning, and now I’ve seen two unlabeled discs deliver PIF Failure counts comparable or in excess of the disc with an intentional imbalanced distribution of sharpie ink. I’m going to finish up my sample of 10 unlabeled discs, and maybe burn a few additional discs with imbalanced ink, but this latest development seems to nuke the whole theory and make it seem more like random disc variation that happened to line up with the ink on the disc before burning. :confused:

However, this is all good data since this project started out with the intention of comparing MCC 004 to Yuden T02. I’ve now seen a fair bit of variation in the MCC 004 media. It will be interesting to see how the Yuden T02 compares.


#16

Variations could be random, but if you don’t give the drive(s) enough time to “rest” between burns/scans, overheating may become a problem and produce worse burns or worse scans.


#17

[QUOTE=DrageMester;2696114]Variations could be random, but if you don’t give the drive(s) enough time to “rest” between burns/scans, overheating may become a problem and produce worse burns or worse scans.[/QUOTE]Maybe, but the worst burns / scans came seem to have come after longer idle periods, not at the end of a quasi back to back run. If anything that would point to a cold drive being worse.


#18

Just for the sake of anyone who stumbles across this thread and wonders why the large amount of testing is required:

I’m going to point out that correlation does not imply causation. You might notice a trend, which may prove to be very valid, but do not rely on that being a rule until you can consistently reproduce that AND other people can consistently reproduce that.

So, you can see quirks like what Stereodude is seeing, but it will take a while to pinpoint what could be causing it, if there’s anything at all. That’s why this thread is great: it’s like one gigantic scientific experiment. For science! :bigsmile:


#19

Well, I think I can safely say that labeling a disc with a Ultra Fine Point Sharpie after burning it has no appreciable impact on quality scans.



#20

It’s not quite as clear here, but it seems safe to say that labeling a disc before burning it with an asymmetrical ink pattern does not guarantee an inferior resulting quality scan. On the flip side, an unlabeled disc won’t always scan better. Does the ink have no appreciable effect on the burn and the following scan? It’s hard to say.