Need opinions and info

vbimport

#1

Hi,

I burned 2 copies of my DVD “Signs” - one @ 2x and another @ 4x…

The burner is a Liteon 812S and the media are the Maxell DVD-R.

I then used Kprobe to scan the media twice - once @ 2x and another @ 4x…

In both cases, the one burned @ 4x performed better, although @ 2x scan the 2x burn wasn’t too bad either…

However, scanning @ 4x resulted in very bad results for the 2x media - high enough that if it were accurate should’ve indicated an unreadable disc

The attached are the files…

Notice for the one titled: Result (Signs 2x), is the one scanned at 4x while the one titled: Results (Sgns 2x @ 2x) is the one scanned at 2x…

My question: is the 4x scanning inappropriate for the one burned at 2x? Should I always scan at, or lower than the speed at which the media was burned (i.e. burned @ 4x, so scan @ 4x or 2x).

Second question: for the 4x scan of the 2x burn, is it accurate?

Looking at my total results, would the 2x burn still be considered acceptable?

Edit: after watching both burns on my computer and on the dvd-player, I honestly couldn’t tell the difference - so does this mean that Kprobe is wrong?

How indicative is Kprobe of the quality of the burn?


#2

Also, people say that burning at slower speeds results in better burns - why isn’t it the case here?


#3

As has been posted before, DVD-R media typically burns better at rated speed. This is especially true of high speed -R. 16x will usually burn a bit better at 8x, but not much better. Of course this varies by burner.


#4

One point is to note the speed range that the media will mormally work over…

Not sure if older 4x drives used a 2x zone at the start, but for all current 4x media, current drives would be 4x all the way.

For 8x media “8x” drives would tend to start with a 4x zone, or maybe 6x - faster drives tend to start at 6x or above and short-step to 8x.

Anything higher, still has to handle the start at a touch below 8x.

Scans are not an exact science, but on each scan, the drive is “calling it as it sees it” - and on those results, the 2x burn does not hold up well when read at higher speeds - cross-check with a transfer rate test - if the drive has to cut speed on the 2x burn, and holds a better read speed on the 4x, that validates what the scan is saying.