Are DVD Disks read from in to out or out to in?

[TomBrooklyn]

Are DVD disks read from hub to edge or the opposite, or some other way?

i.e. Can one glean from where a backup "locks up" and will play no further the approximate location on the original disk of the scratch that caused the lock-up?

[squid_80]

I believe it's hub to edge (inside to outside) since if you only burn a small amount to disc you can see the track on the inside and the outside still looks blank.
Remember you've got the layer break to consider if it's a dual-layer disc and you're reading over the approximate half way point. I think the second layer goes in the opposite direction, edge to hub.

[archaeo]

That is correct, it will burn from the inside out. That's why overburning (files > 4.35Gb) can create increased errors as you move toward the outside edge.

[TomBrooklyn]

That is correct, it will burn from the inside out. That's why overburning (files > 4.35Gb) can create increased errors as you move toward the outside edge.
Hi,
Intuitively, I didn't think overburning would increase errors as you get towards the outside edge, I thought the end of the copy would just get cut off. I don't have any experience with this though as I'm always careful to adhere to the proper sizing.

[archaeo]

Actually most software programs for burning will not allow you to exceed a certain file size for dvd5, so you can't just try to burn say, a 4.7Gb file onto a DVD5 even if you wanted to.
However, even if you are within the size limit (say 4.36gb), you still have an increased chance for errors toward that outer limit.


Excerpt from www.digitalfaq.com
A disc spins faster on the outside than it does on the inside (ask any college physics professor). And round objects tend to be most unsteady at the outside. While DVD media allows for some degree of error (data is written in a "wobble groove"), exaggerated wobble will caused the laser to spew data in areas not meant for writing. It thus disappears, and the data comes up as missing on the disc, resulting in freezing, blockiness and other odd visual errors (caused from the decoder attempting to compensate for material that is missing).

[squid_80]

But you normally have the choice of burning at 4x instead of say, 16x which will lessen the chances of errors being written.

[Boulder]

Burning at too low speeds can cause issues as well. I'd personally use the certified speed for the media in question, or something as close to that as possible.