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rdgrimes wrote:I think what you mean is that your Benq gives you the results you want to see. There's no such thing as "realistic" or "unrealistic" error scans. They are what the are, in whatever drive is used.

Without getting too hung on accurate terms, I also wouldn't trust LiteOn DVD-scans (or any single dvd burner scans).

Why not LiteOn?

They can produce nice graphs even when the disc is at less than good in many other drives (or even down to unreadable).

I have a test set of c. 280 scans (done with seven drives on a multitude of discs) that shows this statistically.

Also, their scans on CD discs are unrealistic.

I have scans from LiteOn dvd-burners that show they returned 0 C1 for a disc read. This is highly unlikely. I'd be eager to say: impossible.

As such, I'm more inclined to side with the argument Doplhinius_rex is making here.

Don't trust a single burner and if you do, remember that LiteOn will most likely give you too optimistic result (compared to a general performance of a large batch of drives).

Halc wrote:They can produce nice graphs even when the disc is at less than good in many other drives (or even down to unreadable).

I have a test set of c. 280 scans (done with seven drives on a multitude of discs) that shows this statistically.

Also, their scans on CD discs are unrealistic.

I have scans from LiteOn dvd-burners that show they returned 0 C1 for a disc read. This is highly unlikely. I'd be eager to say: impossible.

Maybe it´t the problem that Liteon are good readers and read discs that other drives can´t read.

DVD-burners from Liteon are not recommend for scanning CD-media, you have to use a CD-RW-drive.

I´m not sure whether Benq a better scanner is, it don´t like some media that is burned on other drives while this media works good in non-Benq-drives

Scour wrote:

Halc wrote:They can produce nice graphs even when the disc is at less than good in many other drives (or even down to unreadable).

I have a test set of c. 280 scans (done with seven drives on a multitude of discs) that shows this statistically.

Also, their scans on CD discs are unrealistic.

I have scans from LiteOn dvd-burners that show they returned 0 C1 for a disc read. This is highly unlikely. I'd be eager to say: impossible.

Maybe it´t the problem that Liteon are good readers and read discs that other drives can´t read.

DVD-burners from Liteon are not recommend for scanning CD-media, you have to use a CD-RW-drive.

I´m not sure whether Benq a better scanner is, it don´t like some media that is burned on other drives while this media works good in non-Benq-drives

You'll notice that the BenQ DW1640 is able to read many discs that do not scan well even on the DW1640 itself, even at full speed. I wonder if maybe BenQ has gotten a better hold on how to have good error correction, without messing around with error scanning?

dolphinius_rex wrote:
You'll notice that the BenQ DW1640 is able to read many discs that do not scan well even on the DW1640 itself, even at full speed. I wonder if maybe BenQ has gotten a better hold on how to have good error correction, without messing around with error scanning?

My 1640 don´t have problems with media I burned in my old LG 4082

But when I used media from a friend who owns a Liteon, the Benq comes in big trouble and show some very high jitter and slowdown during reading

Scour wrote:Maybe it´t the problem that Liteon are good readers and read discs that other drives can´t read.

Yes. On it's own it's not a problem, but when people with limited knowledge draw conclusions that are not supported by the test setup, then it's a problem.

That's why I don't recommend LiteOn as a scanning drive for testing "roughly generalisable disc compatibility", because it is so much better a reader than the average on the market.

It gives too optimistic figures, if one considers what most people have for readers (most DON'T have a LiteOn or anything else that performs at that level).

Hence, my recommendation.

Scour wrote:DVD-burners from Liteon are not recommend for scanning CD-media, you have to use a CD-RW-drive.

I'm quite aware of that (long before most were, in fact). However, many still don't understand this, nor have I found a good explanation for this.

In this case, the drive is clearly reporting something else than what it is seeing OR it isn't really detecting C1/C2 errors properly at all (i.e. errors that even the reading drive faces are going unnoticed).

I´m not sure whether Benq a better scanner is, it don´t like some media that is burned on other drives while this media works good in non-Benq-drives

Exactly. BenQ is also a very good reader (although not statistically as solid as LiteOns in my own tests).

Therefor I cannot recommend ANY single consumer drive for causal read error rate testing, if one wants to draw any sort of rought generalisations from the results.

Halc wrote:
Exactly. BenQ is also a very good reader (although not statistically as solid as LiteOns in my own tests).

I´m talked to a friend about this, because he had often different drives.

He said that Benq is generally a good reader but very seinstive with media that have high jitter while Liteon-drives have no problems.

On the other hand, LG 4163 produces higher jitter than Benq and the Benq´s have no problems with this media.

His conclusion is that Benq have a Burned-with-a-burner-with-Mediatek-chipset-allergy