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!