Disc Quality & Scanning Errors

vbimport

#1

i’ve spent all morning reading through this site trying to figure out how to test the quality of my burned media, and im a little confused about the results. i’ve been burning mostly with good quality media at compatible speeds (8x dvd 32x cd) with predictable results. however, some of my discs give errors or stop working after awhile, which i associated to cheap media, but with the current relativity of the very term itself i have come to the conclusion that scanning is the only real way to test whether media is good or bad.

for example CMC media is generally bad, but some give very good results.

anyway, here are some of my results:

HP 640C QS12 (a HP640i drive): every dvd gives the “no additional sense information” error, with a cd this error came up about 15 seconds into the test; this is my primary burner, but i take it that it does not have scanning capability.


scanned from my 3550A this time- good media, good burn, good quality. the test reflects this; disc plays fine, no problems.


CMC - definitely questionable media, but i dont get what happened with this test. Scandisc tells me the file is ok and all the sectors are good, while running the quality test on a NEC2510A instead gives me no PIEs, 7 PIFs and a quality score of 73; i guess i can infer that the 2510 doesnt have proper scanning capability either, but whats the deal with the 3550 test?
how can i test the true quality of this media?


prodisc (fujifilm), another questionable media. a quality score of 45 isnt very good, but the PIEs are within the threshold for a good burn (<280), meaning this is decent, right? (considering this is cheap media…)
i havent had any playback problems with this or any fuji burns, both software and standalone, so what can i infer from this test?


#2

A healthy CD should have NO C2 errors!


#3

@lex71x: NEC drives are temperamental scanners at best (and unusable scanners at worst). I suggest trying other scanning speeds such as 12x and 8x. My own NEC 4551 is most reliable when scanning at 12x for DVDs.

For CD scanning I suggest scanning at 32x. You might get random C1/C2 spikes in your scans at any speed on these NEC drives, but for me the 32x scanning speed is least likely to produce random spikes.


#4

so none of my 4 drive are reliable scanners… damn, shoulda bought a lite-on :a

are 4551A’s better scanners? does firmware affect scannability? im gettin one one of these days, i can already tell im gonna have a field day with labelflash :stuck_out_tongue:

oh yeah, and are HP’s completely useless for scanning or am i having other problems?

the speeds i used were the ones the guide on this site said to use (5x for nec, max for cd-r) but i guess they’re not exactly accurate…

anyway, do these 32x results look more accurate? that 36QS doesnt look up to par considering TDK is usually good media even though it is CMC.

even though scandisc surface scan says they are all good sectors, could the usability or copyability still be affected? is this a more accurate measurement of quality? (it showed 282 C1 errors vs 364 using the original DQ test)

8x was almost the same as 5x, it was 43 instead of 45…

at 12x - much better:


#5

with most of my good dvd’s the value is about 7~10, all occurring during the first 1% of the scan… could that just be scanning inaccuracy?


#6

As looney as your 3550 :frowning: (for DVDs - because they’re actually usable CDR scanners).

But these 3550/4550 drives are great for transfer rate tests, they’re very sensitive readers, so a flawless reading curve in these is in general a good sign. It doesn’t tell you everything about the disc quality of course, but neither do PIE/PIF tests. Couple TRTs in the 3550 and scans in a LiteOn or Plextor, and you start having a good testing combination. :slight_smile:

About CMC CDRs being questionable, well, it depends on the brands, as all don’t sell the same grade of CMC CDRs. But CMC CDRS are overall definitly variable in quality, like their DVDRs. Buy the right brands (HP for example) and CMC can show to be quite good actually. But then again, not the best choice considering prices nowadays. Go for the best, like Maxell Pro, Verbatim, unbranded Taiyo Yuden, Plextor… :wink:


#7

from my experience hp is the ONLY good cmc media. ironically, i got these for free.

now, since i dont own a drive that scans accurately, what CAN i do to test my media quality?