Is it OPC [Optimum Power Control] really usefull?

vbimport

#1

I am starting to test the last version of Burnaware and I am wondering if the OPC is really usefull.

I know this feature it is also included into ImgBurm.

I made a couple of test on very bad media, like CD-R made by Verbatim and TDK: without OPC it was almost a disaster, by OPC there was an important improvement about C1/C2 errors.

By using good media like Tayio Yuden there was no big difference.

It seems this technology works by calibrating the power laser and I guess the speed too, but it is also a technology quite old and never updated.

My big question is that I think it works by continuos calibrations (write, read, match, correct and again write, read, match, coorect), producing so a lot of gaps.

Is there anyone with more experience than me who can give me a couple of good advice, pelase?

http://www.osta.org/specs/pdf/opc.pdf


#2

OPC is a quick test that a drive performs before burning the data to the disc. A drive simply burns short bursts at different laser power levels within the power calibration area of the disc and examines the result to fine tune the laser power output for the best burn with that disc. As you discovered, burns with consistent good quality media that has little variation from one disc to the next are often not improved much by this fine tuning. Improvements with OPC are most noticeable with less than great media, just as you have found, or when your burner’s firmware has a less than ideal write strategy for the speed you have chosen to burn at. OPC is not a continuous calibration. Drives like Lite-ons and BenQs have the ability to perform continuous calibration when their hypertuning or Solidburn functions are enabled. This is not related to OPC.


#3

Ok!

Thanks a lot for answering, now everyhing is starting to be a little more clear.

At this point, if I did not missunderstood what you worte, I guess OPC only works fine with either low quality medias or low quality burners… or both.

My burner is a Plextor Premium II and I am wondering if this OPC feature is usefull for this combination or not (burner + media), especially because even if I only use CD-R by T.Y., I can made several test and each time get a different result which voids the former one.


#4

OPC is most effective with low quality media.

A low quality burner (as we see it) would fail to perform a decent OPC, and simply burn with one set write strategy for every given disc model. This would not account for variability in quality of discs or even occasional material changes in the disc model, which makes for bad burns. (Certain LG drives come to mind for consistently butchering certain production runs of a given disc model, only to be fine with other batches of the same model).

“Enabling” the OPC will probably not benefit the Plextor Premium/Premium II combination, simply because one is typically regarded as a very good CD burner, while the other is typically regarded as a very good brand of medium.

Do know that, even without the OPC function “enabled” by software, some drives will still do OPC checks on their own, and with one of these intelligent drives it does not matter whether the software tells the drive to do this or not. If you can switch the option off with no bad effects, it doesn’t matter. If you find that it actually helps, leave it on.


#5

Thank you Albert for your very exhaustive answer.

As I can see with a bad Verabatim burned without OPC I get something like 14,000 C1.

By OPC on, I only get 7,000 (almost half)

At this point my doubt was if it could help with good media and make the burning process even better and I was wondering why there was no difference.
I thought that maybe I was doing something wrong.

Thanks again Albert :wink:


#6

I’ve had this option enbaled as default on some good drivers like Optiarc and Pioneer and when I started getting burning errors with this setting enabled (when disabled no burning errors), the drives shortly after died. So it might also be a good indicator when a burner is going downhill and in the need of a replacement.

:slight_smile:


#7

[QUOTE=cynthia_old;2630097]I’ve had this option enbaled as default on some good drivers like Optiarc and Pioneer and when I started getting burning errors with this setting enabled (when disabled no burning errors), the drives shortly after died. So it might also be a good indicator when a burner is going downhill and in the need of a replacement.

:)[/QUOTE]Funny how stuff like that happens, but it’s true. In my case, it was me trying to burn a few pieces of oddly out-of-spec MCC 003 that didn’t get along with any other drives (no one could figure out why), but leaving OPC enabled in ImgBurn pretty much meant that none of my drives at the time would write to it. This same batch managed to kill a few drives. When in doubt, trust in the OPC to tell you when things are not right. :bigsmile: