DVD-RAM - A Myriad of questions

vbimport

#1

Hello fellow CD-Freakers,

I have a heap of questions and experiences and I’m not sure whether this is the most appropriate forum to post them in, because it spans a wide range of areas but on the subject of DVD-RAM. As a hobbyist, I love the exotic DVD-RAM format - and I have accquired a collection of 13 double-sided RAM cartridges and 19 single sided RAM discs of varying sorts.

There is one thing that troubles me. RAM burn quality. While I do not have a LiteON drive to test with, my laptop has a Phillips SDVD8820 drive that reads RAM and reports quality data. It’s 16ECC may not be the most favourable for quality testing, but it seems to show very many different burn qualities even for the same type of disc and generally poor quality with some media.

I have a batch here of Maxell DVD-RAM 3x [MXL08] which seem to have a problem. Of the 10 discs that i had purchased, two have a pinkish hase in addition to the normal caramel-brown-gold colour of RAM. These two exhibit ghastly burn quality of which I think can be attributed to a chemical change or defect - but what causes this? I intend to backup my data to RAM and wanted to know whether anyone has experienced similar things.

Using the Phillips SDVD8820, it is also established that all the burns from the LG GSA-4163B seem to be TRASH compared to burns from the Pioneer DVR-111L - to the point the SDVD8820 had issues reading the disc, or seeking constantly due to reallocated sectors on a known good MXL08 disc. Seems like LG isn’t the “ram” specialist even though it’s been in the market for a while.

As for quality, I have also noted vast differences in burn quality between the two sides of a double-sided Panasonic 3x Type4 RAM cartridge. And the same of a double-sided TDK 3x Type4 RAM cartridge [MXL7]. This is also interesting - i wonder if this suggests a poorer QC for RAM? or problems producing good double-sided discs?

From my observation - the Pioneer DVR-111L [like most drives] verifies on write as is normal for DVD-RAM resulting in one side writing in ~ 40mins which is 1.3-1.4x for a 3x disc. This is normal. What isn’t normal, is when i use INCD to copy even just a large file, it takes … 90 minutes or so for a side. This is just painfully slow - as if it’s write-verify is being re-verified through software … I’m not sure - but what are other people’s times for these sorts of operations?

Also, RAM is different to other discs in the way the read speed is identical to the write speed for most applications - but seeing as there are 5x RAM discs that read at 5x, is there any chance of breaking some sort of read-lock to allow even older 2x RAM discs to read at 5x … or go one better and give them the whopping full 16x? It’s just unusual - is there any particular reason why the read speed should be limited to the write speed?

I know this is getting long, but I just want to attach a few scans to show some of the results I have been getting from DVD-RAM. I do scans on the SDVD8820 at 2x because it results in a 16ECC readout, I’m not sure what the 3x result would be - but I’d imagine the graph would be worse.

I’m sorry that i’ve full-screened my scans, and will have to resize them, making them look a bit odd, but in order of first to last scan:

Scan 1 is of a MXL8 disc that has the higher error bits written in an LG, with some parts rewritten by a Pioneer. The disc even shows distinct colour differences at the border zones where different drives were used. The SDVD8820 had issues reading it initially and had come up as blank once - so I do put some sort of faith in the error scans. The dips seem to co-incide with seeks which indicate the re-allocated sectors by the LG.

Scan 2 is of a MXL8 disc that’s got a normal colour, burnt in the Pioneer. Contrast this with …

Scan 3 of a MXL8 disc with the smoky pink hazy colour, also burnt in the same Pioneer, same batch brought from the same place with no differences [compared packaging, codes on the disc, mediacode]. The high hump zone was rewritten after an initial write.

Scan 4 is the same MXL8 disc after a near-complete surface overwrite. What a terrible looking scan. Reads OK, but SDVD8820 seems to hang on recognition for a bit longer. Did not complete the scan to save time.

Scans 5 and 6 are of the same Panasonic disc, but of opposite sides. Both sides are new and undamaged and written just once. The first scan has been altered to remove a MSN sign-in notification to protect the identity of the person.

Scan 7 - the final scan shows the second side of a MXL7 double side disc. Unfortunately the scan for the first side was not saved, but it looked smooth and relatively normal. This scan somehow exhibits error spikes which were not present on the first side.

Although I do not have any scans here, because I didn’t save them, it appears that the ram that’s used in TDK is a RITEK DVD-RAM and it’s not very good quality - the burns from this Pioneer appear to be worse than the Maxell and Panasonic [which is sort of expected]. From what I’ve heard and seen from a site that used a LiteOn drive to compare RAM burn quality, a Pioneer burner has better RAM burning quality than any other burner [some japanese site that I don’t remember anymore] so I stick to my Pioneer at the moment.

DVD-RAM seems to be a fascinating media. I really enjoy backing up/rewriting on it and playing with it as a sort of hobby and hope it keeps my data safe, however, it does seem like it has wierd behavior.

I hope to be enlightened or at least to invite some discussion. Thanks for reading all of this!

Gough.


#2

Scans of DVD-RAM don’t mean anything. If you use DVD-RAM only use Made in Japan discs: they are sold by Panasonic, Maxell and Verbatim (manufactured by Panasonic). You do not need to verify discs with any third-party tool: RAM verifies as it writes - if it’s not working for some reason Windows will report an error.


#3

Yes, I do know that it verifies while writing, but all too many CD-Freakers know that even very poor burns can read initially - but as time goes on and the disc deteriorates, even a “once readable” disc that passes a byte verification can become unreadable. In fact, a burn that doesn’t pass the PI/PIF scan tests can verify byte:byte OK if the drive recovers the data, but the problem is - that is only for a limited time. I am trying to establish the actual quality of the burns, so I can comparatively compare different mediatypes and see whether they are in standard and get an indication of which would last and which wouldn’t. Also, it’s nice to have some figures to quantify burn quality - just because it “verifies” in the burner that burnt it doesn’t gurarantee a different reader [with different error correcting abilities] can read the output. Thanks for your input however, and yes, after a bad experience with Optodisc RAM, i’ve stuck to buying Maxell and Panasonic. The Ritek’s [TDK’s] were given to me … :smiley:


#4

Any reason for using InCD over Panasonic’s hacked DVD-RAM drivers?

I’m still a relative noob to DVD-RAM, though I know it’s considered significantly better to format using UDF rather than FAT32 with DVD-RAM media, just in case you’re using FAT32. I’ve used only M01Jxxxx-coded media from Panasonic and Fuji - 2x, 3x, and 5x. They perform very well and the Panasonic discs can be purchased fairly cheaply from their website with free shipping if you join their ‘club’.

I’ve got a Liteon 165P6S that can perform PIE/PIF tests on DVD-RAM media and my results were suprisingly good compared to what I had expected. I’ve got no idea how your scans should be interpreted in comparison, however my DVD-RAM scans on my Liteon rival good DVD-R/+R media scans. I did a number of tests to check burn quality after repeated burns and comparisons on 3 different burners, and to my suprise the quality is nearly unchanged after 5-10 burns/formats/reburns and there was also not a great difference in burn quality between a Pioneer 111L, Liteon 165P6S, and 2 Benq 1670’s.

I think that claiming that PIE/PIF scanning is irrelevant for DVD-RAM media would be false. Yes the media gets verified at the time of the burn, however the reasons for doing PIE/PIF scanning are not to test data readability. It’s for checking burn quality, deterioration levels and whether or not the burns are marginal in quality, etc. - so I think that lui gough basically hit the nail on the head on why it’s still quite valid to test DVD-RAM media. But again, I don’t know how valid the scans with your Philips drive are, I don’t know anything about how trustworthy it’s scanning is. I would suggest you look into a Liteon if you want to take your testing a step further (new Samsung 182x drives may have this ability as well since they can perform scanning with standard DVD media just as the Liteons can). You may be getting overly concerned by judging burns with your current drive, hard to say unless you test with another drive that has a more trusted reputation for testing.


#5

I used my 4163B a lot for RAM writing. Didn’t have a problem with the data on the discs for about 2 years (then I wiped them 'cos I didn’t need what was on them). :slight_smile:

Edit: Panasonic branded DVD-RAM, BTW.


#6

And I was just going to ask. Good Job, Mind reader. :stuck_out_tongue:


#7

LOL :bigsmile:


#8

DVD-RAM is not an archival tool, it’s intended only for short-term stuff, and for re-writing, erasing, etc. In short, it’s meant to be used as a big floppy. It’s totally appropriate for that purpose, and burn quality scans are a waste of time.
The same can be said of RW discs. You shouldn’t be putting anything on either that’s not backed up elsewhere, unless you like to live dangerously. Use them for moving data from point A to point B, weekly backups, etc.


#9

Hmm, well I don’t currently have a copy of the Panasonic DVD-RAM driver, however, I am using InCD because it works with UDF2.0 [which I format my discs with]. I do have Panasonic branded discs, and they work well when compared with the rest of the discs. Maybe the drive is at fault, producing bad scans, but it seems to have some correlation. I might get a LiteOn DVD-Burner to test my RAM burns - which burner? any of the 6s models or 1p models?

As for DVD-RAM not being for archival - I tend to disagree a bit. I did hear that ram has good properties for “always overwrite” situations, however, the write-verify and also background reading-rewriting are more for archival I would think. Also, the greater mechanical stability characteristics demanded for DVD-RAM also make me think of the media as being specifically “better” and the use of a more special recording layer makes me feel somehow more reassured compared to DVD-R [which has failed me in the past … but is getting better as drives and discs improve]. I have CD-R’s which failed through disc rot, however, their CD-RW backup survived, because I would think the CD-RW had better manufacturing standards for rewriting reasons and they held the data just fine through the course of ~ 8-10 years [for the 4x/2x CD-RW’s] and so I have some sort of “trust” in rewritable formats - even though they do say the “phase change” material is less stable. The RAM’s phase change material is meant to be more stable than the others. I do have some MKMA02 DVD+RW discs that have their fringes being attacked by disc rot - so I am losing trust in them - but my RICOHJPNW11 burnt by my first DW400A are still reading much better than the RICOHJPNR01 burnt at the same time [which suffers from read errors at the edge] … so it’s a little complex based on my experience.


#10

It’s complex if you look at things this way. But it’s more simple if you look at it another way: for the cost of 1 DVD-RAM, how many write-once discs can you burn for your archival purposes…?

Long-term, archival, all that stuff, if anyone is really serious about his/her backups, the [I]only[/I] way to go is storing the data on several different media, stored in different places. Trusting just one piece of media because it’s more “stable” or “trustable” is not sound, it’s wishful thinking. You can accidentally drop the disc onto a hard floor… you can accidentally scratch it beyond reason… there are dozens of ways to damage a disc and make the data unaccessible. If the data is on this disc and this disc alone, it’s gone. Forever.

Managing archival backups is not about finding the right media to trust, it’s all about strategy: enhancing the [I]chances[/I] to be able to recover the data in case something goes wrong. When you look at things this way, then you start finding the proper solutions for archiving, raise the relevant questions and forget about the irrelevant ones, like “what is [I]the[/I] media I can trust for my backups”.

Interesting reading on the question: http://free-backup.info/separation-is-critical-to-your-backup-strategy.html - there are dozen of other pages… http://www.google.fr/search?hl=fr&q=backup+strategy&btnG=Recherche+Google&meta=


#11

Wise words, yes I always keep multiple copies at two sites, but I’m always finding that even that isn’t always enough - and so I’m also introducing not just different media but a whole different type of media altogether. Maybe I should have a library of different media to deal with this… no I wasn’t serious but I think that might be a good investment.

Oh and just to add, I do test my discs on a 3 monthly basis, store them in a dark space as close to room temperature as possible. I also back them up to a Hard Disk if money allows, most imporant discs first, and produce a new set of discs every year [as I find discs change, better discs and better burners result in better burns that should last longer]. I just had a thought - maybe storing discs in the freezer [similar to some people storing film to stop chemical degradation] might enhance their life as long as they are thawed first … or maybe it would destroy the data - worthwhile experiment maybe?

Right now - I’m getting my Maxell MXL8 4.7Gb media at AU$2 each and Panasonic 9.4Gb for AU$3 each. TY DVD-R is AU$0.57 and any DVD+RW is AU$2 each. In that persepctive, for rewritability it’s no premium at all - just at the cost of compatibility. Compared to the TY - it’s about 4x more expensive - but I don’t specifically mind this if it does end up saving my most prescious memories.


#12

It wasn’t clear form my previous post I guess, :o when I implied that it’s better to burn several write-once discs rather than 1 RAM disc, I also implied to burn on different disc [I]models[/I]. :wink:

Personal example: for important stuff and/or archival, right now I burn
1 x Ricohjpnr01 (Ricoh) (yes I still have some of this great media that can be overspeeded @12X with great quality :)) => stays home
1 x MMC004 (Verbatim) => goes to a friend’s place
1 x MBIPG101R04 (Imation branded) => goes into the car.


#13

Yep yep, it’s a bad experience that’s made me paranoid. So far i tend to duplicate yearly and check quarterly so i’ll have a farm of discs.

I start like this - say if I started, I’ll burn two sets. The set usually has DVD+R, DVD+RW. Then I check the quality of both sets quaterly - any noticeably defective discs gets re-burnt immediately on whatever quality disc is available. Then every year I’ll burn a new set of DVD+R’s. That means by the end of the first year there’ll be two sets for each set - one set from last year and a new set from this year. Depending on my mood, I might rewrite the DVD+RW - but it’s just there as a “second set” say if worst comes to worst and it’s discovered the disc manufacturing is bad.

So my first pair of sets are on RICOHJPNR01, then the second copy of the sets are on RICOHJPNR02, the third copy of the sets are on MCC003 and this year, the sets will be made onto YUDEN000T03 [for the first time]. The RICOHJPNW11 DVD+RW i employed since the beginning still reads better than the first R01 set, looks similar to the R02 set and hasn’t been reburnt due to time but they are deteriorating slightly.

I’m experimenting with DVD-RAM as a “third option” - that way I’ve got nearly everything covered for a third time. If it ends up that it’s more stable than DVD+RW [which I imagine it is] and doesn’t need to be reburnt then it might end up outlasting some DVD+R generations.

You are right though, I should try different media - and make more copies at more frequent intervals - but when backing up 35 discs … i’m tempted to be lazy.


#14

Woa, looks like I quite underestimated your seriousness and dedication for backups! :bigsmile:

Now I see where you’re heading to with RAM. But as you mention, probably you’re taking the overkill route from paranoïa because of your bad experience.

Frankly, if your routine is burning anew each year, any write-once media is stable enough for the purpose (well maybe except Ritek G05 :bigsmile: ), assuming it’s been burnt properly. I haven’t had any media (except… you know what lol) unstable enough to have a lifespan under a year, not even the ones that were burnt in the worst conditions (then again, apart from G04/G05 and a pair of GSC discs, I have always used reasonably good discs).

but when backing up 35 discs … i’m tempted to be lazy.
I so understand that. :slight_smile: - that’s actually another of the reasons why I prefer write-once: saving time. I can burn any MID I use for backups @12X. Latest RW maxxes @8X (if I’m not mistaken), for 1 disc it’s no big deal, but for full backups it makes a real difference. I think the saved time from switching to write-once allows for the burn of an additional set., which is even safer. :cool:

Have it your way of course. :slight_smile: - besides, I realize that I have once again drawn the thread off-topic, sorry about that, :o but as your original input was motivated by backup worries, I guess I haven’t been too much out of line…


#15

LOL - not at all. Enjoy any input - much better than silence. It’s more experimental at the moment - since I’ve heard freezing film in special ways helps prints and films to last longer [less energy for chemical reactions to occur] - i don’t know - i might freeze a set and see if it lasts longer. The RAM is just another format - another possibility - just want to gather as much knowledge as possible. And I burn all my backups at 8x for write once partly because I’m not confident with the jitter readings for 12x burns. I honestly like all jitter < or = to 10% [Benq 1640] because they tend to be a lot more stable over time. 12% works fine, but when it exceeds 12% i find picky readers won’t like it. However, i’ve had a very shocking burn with 220 peak PIF [Not PIE] being recovered by the BenQ at 1x readback or something - so I think my strategy stands a chance of securing the data for a long time, even if I forgot to migrate sets for one year - or had to wait 0.5 yr. I did have some discs that sort of destroy themselves - say in a set of 50 - there’d be one RICOHJPNR02 that’d be totally bad for some unknown reason - even though initially they all scanned the same so :S

However, it seems annoying that RAM can only be read at the write speed. I think this can be fixed - because no other format seems to read at the write speed - does anyone know why?

As for the maxells - there are MXL8 that i have that differ in surface colour - has a hazy pink colour - has any other RAM user spotted this occasionally with a few MXL8’s?


#16

How’s this 12X burn of jpnr01 in your book? :stuck_out_tongue: (1650 BCDC) - (the max value are glitches from the 12X scanning speed)



#17

I think there may be certain drives that can read slower media at faster than their burn speeds, but I’m not sure on that. Before I decided on another burner and before I bought any DVD-RAM media, I basically looked at every DVD-RAM test done with DVD-RAM Drive reviews here at CDFreaks and that was one of the things I was thinking about as well. For some reason I thought at least one of the drives was able to read some media faster than its rated speed but you’ll have to look through the tests.


#18

@ Francksoy - WOW! That is impressive. When i brought my pile of burners, I stuck on the decision to go for MANY 1640 drives because that’s what was there, and was supposedly good. So i stopped there. Never brought any until the DVR-111L [now I’ve got two]. That jitter is amazing - but that’s probably explainable because the wierd “stabilises - then dips back down” strategy of 1640 on 8x/12x doesn’t exist on the 1650 [which looks like the more common P-CAV method]. It’s usually on that segment i see a marked increase in jitter or at the end. This is SB on correct? I like to leave SB on for all media, but i’ve burnt a lot for friends and so the 1640’s seem to learn wierd - maybe the laser is wearing, I don’t know :S.

@scoobiedoobie - In terms of reading faster than write speed - that’s probably only occurred seldomly for 2x / 3x ram. I have some 3x marked ram that only writes at 2x [burner won’t budge] but reads at 3x - but since there’s 5x ram that can do P-CAV - I think that it’s possible to go faster than the drives will let us. DVD+RW’s used to be limited to 8x read by some drives due to reflectivity - yet the read-hacks show - 12x / 16x is possible depending on the circumstances - so I hope there might be a little more technical explaination as to why this sort of thing is occuring.

I do wish more people would embrace the DVD-RAM format though. I see it’s merits - in drag and drop and i’ve grown to love the discs to an extent - especially since i’ve got a pile of hard drive storage and write-once is relegated to backup. I do hope there’s someone out there who can answer the technical side of things - maybe CK or Ala42 might be able to help?


#19

[OT]
Not to discount the merits of SB, but I did quite a few tests in my 1640 about a year ago and I actually found that it created, at best, similar results to SB off and actually created slightly worse results in many cases. Suffice it to say that while SB can help, it doesn’t necessarily always help your burns and if the drive has a decent stock write strategy as the Benq drives usually do, SB may not be something to use. But don’t decide from my results, try some comparisons yourself with your media and burner(s). Interestingly, my 1655 did seem to slightly improve the results with SB on for a couple of tests I did so the drive model and firmware can be factors.[OT]


#20

[OT]
My experiences with SB initially were good when it came out - betters the original strategy - or strategy swapping for overspeeding - however as the number of burns increased, the strategy started going haywire and the ends of discs started to fall out of spec / the beginning developed a hump etc. I wasn’t keeping a close eye on a pair of 1640’s that had SB on/on becase OS was on and they seemed to drift quality a bit. But then I turned the SB off … some of the burns were totally trash immediately as soon as they came out of the burner [cmc stuff] whereas they were initially great, then got mediocre with SB on. Cleared SB mem, all is back to normal, drifting to bad slowly just like my old LiteOn. I think due to the burning volume, the laser is suffering decay - time for a new burner maybe. And I like speaking offtopic - something to talk about especially because I don’t think there’s much more DVD-RAM knowledge out there … but it’s a shame BenQ stopped with their optical drives - when LiteOn took over, BenQ dissapeared. Is the HT on LiteOn like a SB for MTK chipsets?
[/OT]

Just tried quality testing with the Pioneer DVR-111L - stalls when starting scan, and when it does start, it only gives a sequence of spikes [probably at the end of each zone] all about the same height. No useful data, I didn’t save the scan. Looks like I might be heading out for a LH-16A1P because it’s available locally at a “good” price. Any suggestions? [And it’s unfortunate that the LH-20A1P isn’t available here. I can’t brag about having the “fastest” burner …]

Meanwhile, in regards to an earlier comment that after many rewrites the error rate was pretty much the same - funny how my scans seem to be able to pick out the rewrite zones, and even under a halogen light I can spot them at times. The fact that “something is different” between the rewrite zones suggests that the DVD-RAM calibration zones might not be so good to help achieve perfect power even with “random rewrite”. Maybe this drive is hyper-sensitive, however, the correlation of higher-error-value on the scan to the zones which have been rewritten more seem to suggest that the drive is at least looking on the right “track” [no pun intended, but what the heck].

Oh and add this question for the experts: Say if a disc has a write error/verify error during operation because of a “temporary defect” - say dirty disc, or dust particle - and the sector is reallocated in the defect management table. The sector isn’t REALLY bad in this case, because next time I put it in, dust could have shift/i could have cleaned the disc. Is there any way to restore these sectors/retest them?