Ive come across a strange problem.

This is one of my best scans ever especially where PIE is concerned but both my BenQ 1620 and 1650 can't read it back

Its Ricoh branded Ricohjpn R01 4x +r. Burned at 8x in the BenQ 1620.

My LG 4167b has no problems reading it and neither does my picky player strangely.

Makes me think i should do transfer rate tests as well as quality scanning. Or probably just the transfer rate test.

Anybody else got any discs that give excellent scans but wont read back properly?

Scan on my BenQ 1650
TRT in the 1650 (same results with the 1620)
TRT in the LG 4167b

If I'm not wrong, DrageMester already pointed to this problem and posted some examples in another thread.

I always do both TRT and scan

I'm sorry about your problem, but i think at least it will make you believe what I have to say next.

In my experience the BenQ 1655 is the pickiest reading drive I have (at least for recordable DVD media) with the possible exception of a 5 year old laptop combo drive (Matshita SR-8175).

There are discs burned in my NEC 4551 drive, my Matshita UJ-840S laptop drive and my LiteOn drives that the BenQ drive cannot read, and no other drive has any problem reading those discs - except in some cases my 5 year old Matshita SR-8175.
Using PIE/PIF(/POF) tests to determine readability is not a workable solution on BenQ drives, NEC drives or LiteOn drives in my experience. It's possible that Plextor POF reporting is reliable enough for this purpose - at least I havent seen any problems with it yet.

The only safe way to test readability is to actually read the disc, and a Read Transfer test (TRT) is an excellent way of doing this.

Given the choice between a disc with good TRT and bad PIE/PIF scan, and another disc with bad TRT and good PIE/PIF scan, I would choose the good TRT every time! (but I want both).

Look here. The scan is not excellent, but the unreadable sectors are located in an excellent part of the scan - the ugly part of the PIE/PIF scan doesn't result in any reading problems!

You convinced me quite some time ago. I don't regret it.

@Chancoluuk: I liked a recent input from Debro (and JayC30) in the BM section: http://club.cdfreaks.com/showpost.ph...1&postcount=30

Here is an excerpt:
A PI/PIF scan with excellent results does not mean that:
* what's on the disc is right.
* the disc is going to last more than a week.
* the disc is going to work on every device you put it into!

This said... for those of us who have several different drives, such issues (I mean such as the one you experienced) are not really a big concern. I don't think that any disc with a good PIE/PIF scan in a reasonably reliable scanner could be unreadable in ALL drives...

@all, this is actually not an uncommon issue with drives that able to do high speed reading, including BenQ and NEC. High speed here means 16x DVD±R and 12x DVD±R DL read speed. Although I must admit that sometimes BenQ will be overly sensitive, while not with NEC due to, IMO, has different correction system (different hardware).

While chancooluk sample is a good way showing how picky his BenQ is, however comparing 16x read with 12x is not really *valid*. This issue has been brought up by rbrtpl in a different way in this thread: testing benq 1650 reading?

If your BenQ is overly sensitive (mine does not), you can always lower the speed read to 12x and most of the time will overcome the problem (look at rbrtpl thread in the above link).

Another way to compare is by doing TRT on the same disc with a NEC @16x.

I was betting on a corrupt firmware flash or bad drive?

My 1650 and dvdd set for 4x read speed are recovering otherwise unreadable disks

your advise Zevia led me to that discovery

Both my BenQ drives wont read the disc. Not just the 1650.

Ive tried the read speed all the way down to 2x and it still wont read it.

Both drives have no problems with any other disc ive thrown at them. Apart from some crappy fake media that failed during the burn.

As long as i can watch it and get the data back using my LG then im fine.

I just wanted to make the point to people around here that Quality scanning probably isnt all that its cracked up to be. That doesn't mean i wont still be religously scanning every disc i see.

how's that disk scan with the 1620?

Quite a few of us have been trying to do that for a while now. Unfortunately it takes a while to learn. I am with Drage on the fact I use both TRT and DQ test. I always keep a DVD-ROM available for occassions when my writers won't get data off a disc, it sometimes does, though not 100% of the time.