Should I be worried?

vbimport

#1

Should I be worried of these spikes at 6,7,8 in the beginning of the burn?

Otherwise the PIF Total is very low.

Link to the scans: http://club.cdfreaks.com/showthread.php?p=1016172#post1016172

/jegus


#2

I wouldn’t be. That is still a pretty good burn.


#3

Since the spike is always in the same place, it’s probably a very minor stamper defect. We’ve all seen Fujifilm-branded YUDEN000T02, stamper code TG001125 media from Best Buy with this sort of spike at 0.5 GB. There is absolutely nothing to worry about, unless your goal is to create scans for the hall of fame thread.


#4

I don’t see any reason to be worried at all. Those are isolated spikes, meaning those could be showing up because of the 8x read speed; at a lower read speed, they might not show up. Besides, sometimes a spike could be caused by some particle of lint or dust at that one spot, also. I would only worry if it was consistently above the limit of 4 for the whole scan…although I’ve seen people have several spikes in their scans to 9-11 on NEC burns, yet still have a good burn that played well in their DVD standalones


#5

agent009: what is an stamper effect? never heard of it. does it indicate bad quality media?


#6

Manufacturing DVDs is similar to stamping coins; metal stampers mold polycarbonate plastic substrate. DVDs have a wobbled spiral track (not unlike vinyl records) pressed into the plastic by the stamper. If the stamper is not perfect (and none of them are, really) you get some groove imperfections, a fraction of a micron in size, that interfere with data synchronization along the groove during recording. That occasionally results in a few thousand erroneous bytes here and there, and is corrected during reading by the error-correcting code. One stamper is used for tens of thousands of discs, so you see the same microscopic defect repeated in all discs you get in one spindle, resulting in the persistent spike that you noticed.

I didn’t mean to say that the discs are defective in any way. They are not pushing the error-correcting code anywhere near its limits.


#7

those scans look fine


#8

Thanks a lot guys!
One thing less to worry about! : )