Tsketteler
Forum Replies Created
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Got the discs today and ran on the CATS tester. They show a POF at the location indicated by the drop in your Eclipse performance analysis…
POF = Parity Outer Fails – The decoder was unable to correct the data using the outer parity codes in the first pass. The wording “first pass” is important because the decoder may be designed to do several passes of error correction. There is a possiblity that the error may be corrected in following passes. This explains why your problem doesn’t show up on every drive.
POF is measured over 1 ECC block and the highest possible value for this parameter is 1, which indicates a probable uncorrectable error.
POF should never be present on a DVD!
There are a few other parameters out also… Bottem Jitter, Radial Run Out, and DPD amplitude (related to the RRO) These aren’t real bad and shouldn’t be causing any problems – the problem you’ve had with these discs is caused by the POF.
I just faxed a copy of the test summary.
Best Regards, -Scott
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I notice there is a red flag on the Eclipse analysis tab… If it’s a tracking servo error or unreadable sectors then you’ve probably got POF errors. When the Eclipse software has trouble reading a disc it keeps dropping the speed down until it can recover the read or can’t and then will report some type of read error.
The graph from the screen shot shows that the disc has a defect at that specific radius on the discs – either a dent causing a spike in radial noise and/or there might have been a scratch, spot, pinhole, etc on the stamper or mirror block causeing a spike in digital errors (PIE, POF, PIF).
From what I’ve seen & read here your problem is a manufacturing/replication defect. Visually check the disc around this location, looks to be around radius 35 – 40mm for a defect. When I get the discs I’ll run them on our CATS system and see exactly what’s up.
If you’d like you can call me at 763.449.5577. Also, we have a website http://www.ads-cd.com but it seems to be down today – they’ve been upgrading our T1 lines…
Best Regards, -Scott
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I run the mastering dept at a CD/DVD replication plant and if you’d like you can send me one of the discs and I’ll let you know what’s wrong with it – no charge.
Scott Ketteler
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2155 Niagara Lane North
Plymouth, MN 55447-4654