NEC PI/PIF giving false readings?

vbimport

#1

I refer you to this http://club.cdfreaks.com/showpost.php?p=975190&postcount=59

On the 3540 it shows up to 300 but on the Benq 1620 it’s much much lower.

Anyone care to explain the huge discrepancy?


#2
  • [i]“Beauty is in the eye of the beholder.” :wink:

[/i]The drives are just reporting what they see, and sometimes one drive will be much better at reading a certain disc than another drive. The NEC burners are not especially good readers.

The disc in question is of marginal quality and the BenQ has no problems reading it, while the NEC drive doesn’t like it very well.


#3

So basically PI/PIF testing is worthless on NEC’s as they are pretty poor readers compared to say a Benq? Might as well get a Benq for testing in that case.


#4

NEC scan fine. just differently.


#5

Correct, its all a matter of interpreting the result. If you know how your drive scans a disc, it really doesn’t matter which drive you use.


#6

So what is a bad scan on an NEC? Anything with an average PI count of over 300???

Edit: Actually perhaps the question is what is a GOOD scan? Anything with an average PI count of between 100-150 (Since my best discs burned on my 2500 scan in the 3540 with an average PI of 100)?


#7

First you have to specify PIE or PIF.
PIF is much more important than PIE.
But the peak valueas are the most important, not the total count.

Sascha


#8

conclusion: a NEC drive is better able to detect a crappy burn than a benq :stuck_out_tongue:
(is the bottle half full or is it half empty?)


#9

OK just burned my first disc in the 3540. I think this is a good scan. Problem is when I scan discs burned by the 2500 I get terrible scans. But I know the discs are not that bad. I tested them in my Lite-On using Kprobe (Granted it was a DVD-ROM with the drive slowed to 4x so not entirely accurate but gives a reasonable proximity) and never got such crappy scans.

Datasafe @ 8x


#10

I agree that this is a good scan.

Can you show us some of your NEC 2500 scans?


#11

Same media burned @ 8x on 2500 with 2.F9 modded firmware. I’m pretty certain the quality of the burn is not as bad as the 3540 is reporting.


#12

I have to agree with bertrik, and I don’t even have to add a smiley!

What is the purpose of scanning your discs?
A. Get the lowest numbers possible so you can “compete” with other forum members about who has the “best” burn.
B. Predict whether your disc can be read at a later time and in other drives.

If your answer is “A” then you want a drive that is very optimistic about what it reads.

If your answer is “B” then it is a blessing in disguise to have a drive that is not an especially good reader, and will consequently show any problems with a marginal quality disc.

It’s a bit like having a canary in a coalmine (the bird, not the single by The Police) - if the canary croaks, you know the air has gone bad. The canary is supposed to croak before you do, not the other way around!


#13

OK just to add to the fire.

2 scans in succession of the same disc. 1 with default CD Speed ECC setting. the other with 1ECC (Or at least I think it is. DWORD value of 1 in registry right?).


So 1ECC looks a better scan (More accurate?) from what I see. Well maybe not since the max PIF is way above 15. Kinda confused to be honest :slight_smile:


#14

Drawing any conclusions about a drive’s error reporting based on a few discs is pretty foolish. Comparing scans done in different drives is equally pointless.
It seems we are constanly reminding that what is reported in scans is not on the disc, but occurs in the reading process. Confirm questionable scans with a transfer rate test if you like, but there’s no such thing as an “unreliable” scan.

Calling a drive a good or bad reader based on scans is also a serious over-simplification. Only a transfer rate test or Scandisc test can determine a drive’s ability or inability to actually read a disc.

Discs that give widely varying results in different tests or different drives are almost always discs of marginal quality that may have a variety of issues. Those issues may or may not be related to actual burn quality. More than likely a combination of issues will come together to make a disc problematic, and again, burn quality is only one of them. Error scans are not reporting burn quality directly, and any of those “issues” can translate to high error rates.

One drive may have an enhanced sensitivity to one of those potential issues, where another does not. This is equally true of 2 drives of the same model, as it is of 2 different models.