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View Full Version : C'T: again DVD±R/W media test


alexnoe
23rd October 2003, 14:22
Tests:
- recording on 3 different recorders and analysing error rate, tracking , HF signal and jitter (they gave a 'score' for error rate and HF signal for each of the 3 recorders, and one for tracking, resulting in 7 categories where to give score). '--' = very bad, '++' = very good, '0' = somewhere between good and bad...
- recording RW discs 10 times, where they wrote k*400 MB in the k-th rewrite cycle
- rewriting 400 MB 1000 times and then check error rate

Results:

Princo 2x DVD-RW
The PI sum 8 max was far over 1000, the jitter was unbelievably high, and the HF signal unbelievably bad. They gave 7x '--'.
That means, when speaking about "DVD-RW" discs, those will be excluded...

DVD±R
As always, a few -R are good (MCC, TY, TDK etc), and a lot of the really cheap and bad stuff (Princo, LeadData...).
For DVD+R, there was no real crap. Out of the tested discs, 4x MCC discs could be recorded at 8x at pretty good quality, while Ricoh discs resulted in very poor recording quality at 8x. Well, this can happen when hacking 8x writing to 4x discs...

Among the tested +R media was only Ricoh, TY and MCC, but none of the newer cheap stuff. Maybe the save that for the next test...

DVD±RW
When recording the discs with k*400 MB in the k-th pass, 4x+RW recording failed for all discs (quote: 'We have never ever seen such bad error rates and jitter values on any test discs'). Only the Philips +RW discs had an error rate which was within the specs after that, but still far too high for 10 rewrite cycles. The laser power was appearently not properly adjusted for parts of the discs that have been used more or less often. However, if I read it correctly, they used only the Plextor drive for this test, so it could be that its firmware is b0rked.

DVD-RW discs did not show this problem, except for Princo of course.

The following discs could be written 1000 times with acceptable or good error rate:
MCC -RW
TDK -RW

The following discs could be written 1000 times, but with bad error rates at the end
Ricoh +RW ('Ricoh')
Philips +RW

The following discs failed before 1000 times
TDK +RW ('Ricoh')
Ritek -RW ('PrimeOn')

coona
23rd October 2003, 15:27
Thanx for info :).

Could you post a link (if it exist in electronic form)?

TIA

alexnoe
23rd October 2003, 15:41
I only have the printed version, using real good old-fashioned paper *cough*. I don't know if they release it also as online version :mad:

netterpaladin
25th October 2003, 18:10
They also tested the DVDs with kprobe and compared the results to the ones from a testing institute. If i recall correctly only 2/3 of the kprobe results were similar to the professional testing, while 1/3 gave wrong results. If that is true, it seems to be a waste of time to use kprobe to check your disks...

netterpaladin

alexnoe
25th October 2003, 18:34
Yeah, and they only tested KProbe with the LiteOn 401S. Some people on Brennmeister also got nonsense results with that drive on KProbe... but since KProbe only reads some RAW data which the PUH is sending, this does not allow conclusions as to the usability of KProbe on other LiteOn DVD-ROMs.

Also, on DVD-RW media, the reading speed really matters (CD-Bremse can set the speed even for DVDs). They did not write whether their problematic results occured on R or RW media, and neither did they write whether they reduced the read speed or not. So all we know is that they got weird results with KProbe on 1 drive with some discs under mysterical circumstances...

gooki
26th October 2003, 21:40
alexnoe does it state how many re-writes the ritek discs managed before they failed?

Just asking as I'm loloking at buying a 100 od RW discs, and as long as it's around the 100 rewite area I'll be happy.

alexnoe
26th October 2003, 21:48
408. But don't forget that Ritek is not know for constant quality. I would not buy them....

I've just received some Verbatim 2x -RW and Ricoh 4x +RW on my own, and I can tell that Verbatim 2x -RW give really good results :-)