how long does it take to burn at different speeds.

[stackner]

i currently have a 4x burner. i am thinking of upgrading to an 8x or 16x burner but have heard that an 8x is still going to take about 10 minutes and it will take a 16x to burn in bout 7 minutes?

so how long should it really take to burn a FULL disc at 8x and 16x?

and if what i have been told is true why does it take a 16x (4 times faster than a 4x burner) to burn a full disc in about half the time a 4x burner takes. seems pointless to upgrade even with dual layer due to dual layer disc's not dropping greatly in price yet.

[jimmalenko]

What you have been told is correct, and for want of a more scientific reason, an 8X or 16X burner does not burn at that speed for the whole entire burn. Moreso, that is the maximum burning speed it will reach, normally from about 40% of the way through (give or take) onwards. There is also the issue of lead in and lead out, whcih I believe is written at the same speed by every burner, regardless of its burner rating. So it is only the actual data that you are burning that can take advantage of the maximum speed your burner can reach, and it takes a little time to get fully would up to this speed. That is why the burn times are disproportionate.

[Capmaster]

It may very well be that the burners can't spin up the disc fast enough to start at 8X or higher.

At a given spindle speed, closer to the center, the disc is passing past the laser at a slower rate. As you move outwards at that same rotational speed, the "real estate" you're covering is greater (higher linear velocity). So when you pass a certain point, the linear velocity is high enough to warrant "shifting gears" to a higher speed.

Just a guess, and I may be speculating from my nether regions

[jeanl]

It may very well be that the burners can't spin up the disc fast enough to start at 8X or higher.

At a given spindle speed, closer to the center, the disc is passing past the laser at a slower rate. As you move outwards at that same rotational speed, the "real estate" you're covering is greater (higher linear velocity). So when you pass a certain point, the linear velocity is high enough to warrant "shifting gears" to a higher speed.

Just a guess, and I may be speculating from my nether regions

capmaster, that's exactly the reason. You can't increase the angular velocity high enough to reach sufficient linear velocity for higher-rate burning at the start of the DVD. It's simply a mechanical problem. I got that info from a friend who makes microcontrollers for DVD drives.
Jeanl

[Capmaster]

It may very well be that the burners can't spin up the disc fast enough to start at 8X or higher.

At a given spindle speed, closer to the center, the disc is passing past the laser at a slower rate. As you move outwards at that same rotational speed, the "real estate" you're covering is greater (higher linear velocity). So when you pass a certain point, the linear velocity is high enough to warrant "shifting gears" to a higher speed.

Just a guess, and I may be speculating from my nether regions

capmaster, that's exactly the reason. You can't increase the angular velocity high enough to reach sufficient linear velocity for higher-rate burning at the start of the DVD. It's simply a mechanical problem. I got that info from a friend who makes microcontrollers for DVD drives.
Jeanl

Ahhh, makes sense. Thanks jeanl