Dvd-ram

vbimport

#1

I have two DVD-RAM discs that I’ve burned on an LG H42N. Both discs are 3X Optodisc MID, one is single sided 4.7gb, one is double sided 9.4gb.

Both appear to be working fine, Windows Autoplay detects the correct type of file, and TRT tests on both discs appear okay. The scan results (scanned on a Liteon 20A1H) are very sporadic however. One side of the 9.4gb disc shows PIF errors > 200, and PIE’s > 1200 for the first ~200mb. The other side appears fine with PIF < 4. My single sided disc has an area of a high PIF clump (PIF ~10), with no visible scratches or surface irregularities on the disc.

Should I trust these scan results? The data stored on these discs are an important hard drive backup, and I’m very leary in storing data especially on the side of the disc with the huge PIF mess. Or should I trust the TRT results which appear completely normal with no slowdowns?

Any recommended DVD-RAM media other than Optodisc? TIA.


#2

I’m not exactly sure that scanning works on DVD-RAM properly, maybe someone can confirm.

But if that media really did have 200+PIF in one spot, it certainly would not TRT perfectly, that’s for sure.

IMO I would trust the TRT tests.


#3

I would not personally feel too confident in Optodisc’s -RAM media over an extended period, their recent +/-R media can be pretty good but their older media was poor, both their -R and -RW. Regarding scanning of RAM media, I don’t really see reason why its value would be too much different than ‘normal’ R and RW media. While RAM is verified by default while it’s being written and damaged areas of the disc may not actually have data written at those locations, I think that a poor quality scan is still a bad sign with RAM, just as a good scan would be a positive sign. Of course a completed TRT means what it means, a fully readable disc, it doesn’t necessarily mean a great burn (and also consider how much slower DVD-RAM media is read compared to R/RW media, excluding 12x discs). Having said all that, just as was brought up recently regarding scanning of RW media, I’d personally be a lot more lenient towards what I’d feel was ‘acceptable’ in a -RAM scan compared to a standard +/-R disc. I do get excellent scans with my 2x, 3x, and 5x Panasonic RAM discs though (scanned in a Liteon 165P6S). For good RAM media at the best prices I’ve seen, order from Panasonic.com and join ‘Club Panasonic’ for free shipping. 3 packs of 5x for about $9 shipped, 15 packs of 3x for around $20 shipped, single 2x discs for around $1 shipped, etc.


#4

I would only buy Maxell or Panasonic -RAM discs to be sure. Any MIJ -RAM is AFAIK either Maxell or Panasonic. For -RAM also be sure to use the RAM drivers for Windows and format the -RAM as UDF 1.5 with the perform physical formatting option before using it a second or third time for backups.


#5

I’m currently using Vista which AFAIK supports RAM natively, and the discs came formatted UDF (which version, I don’t know) as default.

What boggles me is that one side of the disc is not completely full (maybe 85% full), however the scan goes the whole length of the disc, which approximately 15%, or the empty portion is covered in PIF and PIE errors. Could this be the culprit? Equally confusing, is that the TRT also covers the entire length of the disc, yet only shows minor slowdowns not related to the unwritten (error filled) portion.

The other side of the 9.4gb disc (it’s 99% full) shows acceptable results. Scans were done on my Samsung drive, but I ran one in the Liteon, and the results were nearly identical (both Mediatek chipsets).

I scanned the single side disc, and the scan came out okay as well as the TRT, so I didn’t save the images… But the four images shown are the TRT and scan of each side of the 9.4gb disc… Any idea why the 200+ PIFs on that one side, and why the TRT shows a successful read?

The idea of using this media, is temporary archival purposes. I routinely back up my hard drive (the one that holds important media, not my main OS drive) every month or so, so I’ll need to restore from these discs in the unlikely event that my Raid 0 array fails. I don’t need something that will last years. Is DVD-RAM a good candidate for this application?


#6

Your second scan looks fine. Your first scan looks fine in the central portion, the outer portion is probably just being thrown off by the fact that there’s no (user) data written there - try a FULL format on that disc and rescan it. The start of your scan also looks like some of my discs’ scans, I’m not sure what the explanation is but I recall a couple of my discs had very high errors for about the first 20MB so I just started those scans at around 20MB - I don’t know if it’s some kind of data related to the formatting or what the reason is. I’d still rather use Panasonic’s discs myself, but your discs look alright. A few odd dips in the first TRT, most of which also show on the quality scan, not sure what to make of those (are the discs clean?).

As far as your usage of DVD-RAM, I think it’s a logical way of using it, IMO more trustworthy than RW media at least (that or just use a good +R/-R disc for your monthly backups).


#7

I’ll have to run a second scan while changing either the min/max graph levels, or the start/end position to see how the scan correlates to the TRT. Otherwise I’m not sure why the speed dips are present in the TRT, these are relatively new discs with no scratches / fingerprints, they’ve only been written once and are stored vertically in a jewel case. I suppose as long as the TRT shows okay, I’ll continue to use the discs until I can get the Panasonic discs to arrive.

I appreciate the suggestion to order from Panasonic.com, that’s the cheapest DVD-RAM media I’ve seen so far… I actually ordered my Optodisc media from www.shop4tech.com when they had the 10$ google checkout deal, so it was only a dollar or two per disc… But something faster would be nice…

Is the good scan shown about (~15k PIF) okay for this type of media? Seems outrageous in comparison to even my worst DVD-/+R media (sony16d1) @ ~4k PIF.


#8

DVD-RAM Discs should be self error correcting so…