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Blu-Ray DVDs Hit 100 GB
Xesdeeni writes "According to The Register and MacWorld, TDK has unveiled a Blu-Ray DVD with four layers that will hold a whopping 100 GB of data. This is shortly after the previously reported HD-DVD announced three-layer HD-DVD that would hold a "mere" 45 GB. Unfortunately, this is also on the heels of the news that the HD DVD unification talks have stalled."
We already have problems with DVDs and CDs going bad. From what I've read, the Blu-Ray discs may be even more fragile due to their extremely thin protective layer. If I am to pick between the two coming standards (Blu-Ray vs HD), I'll choose the more reliable one.
Maybe this is a dumb question, but if the surface gets scratched, wouldn't it prevent all layers from being read correctly? I guess if there was an offset on the layers, you could create some kind of raid structure on the disc. Chances are that if each layer is offset by 180 degrees, the scratch wouldn't harm both copies, but at that point I wonder if you would be sacrificing performance to the point where the disc is too slow to use anyway. If it had to scan the disc, decide if the data was readable, if not find the other copy, and the use that, it might not work too well. Also, writing your data would take twice as long. They already say it will take over an hour to write an entire disc but if you only need to write smaller files on it, each file will take twice as long.
100gb is nice and all, but if you can't rely on these for more than backup due to their fragility why not just go RAID 1 and get some extra read performance at the same time?
These are nice for movies, but DVDs scratch badly as it is. I don't want something even less durable.
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I'm a composer/producer. It's actually as easy or easier to make a surround mix than a stereo mix. /.) and entertaining, there really is no reason to pay for the equipment/setup, and therefore no reason to spend the extra bucks on the higher quality discs.
But it's difficult for the average consumer to have a playback system that makes it worthwhile. You have to spend a few thousand dollars, and have the right room, and then spend your time sitting in the sweet spot to listen to your music.
If, like me, you listen to music while driving, exercising (oh wait, this is
Yes, but data integrity is the real key.
I've been burning DVD+-R's (4.7gb) and when I run the "verify data" option to confirm a good burn, the defective rate on my DVDs is about 1 in 5. I've had situations where the DVD burns and verifies perfectly in the burner but I cannot get it to read in another DVD reader.
Then there is the question of DVD rot. A DVD is a sandwich of two plastic layers. There is the possibility that the cement that binds these layers can become unglued.
For routine DVDs, I find myself burning 2 copies to be safe. For important DVDs I burn 3 copies (and use media from different manufacturers).
My primary DVD burner is a dual layer burner but I do not trust DVD media enough to burn dual layer discs. These 3 and 4 layer discs leave me wary of their long term reliability.
As a data addict, I feel I must weigh in here. There are a few concerns:
Migration
I have switched exclusively to recordable DVD for backups about 20 months ago. The extra capacity was dearly needed, as my CD-R collection was growing large by bounds and leaps, making it unmanageable. At first, like everyone else, I thought whoa - 4.37GB - surely nobody will need more that than. Famous last words.
What was interesting to observe is that a) the transition to DVD from CD-R happened faster for me than from previous backup mediums to CD-R (Zip disks, MO discs, etc.). Whereas I had used CD-R in conjunction with my previous mediums for quite a while, jumping from CD-R to DVD-R was much quicker. About the only things that held me back are the fact that most OS installation media are still CD-R images, and the fact that the mp3-capable HU in my car only reads CD-R. That's why I still stock CD-R, otherwise I would have none.
Capacity
I felt the capacity of DVD-R as being limiting much quicker than I did so with CD-R. In other words, 4.37GB "got small" much faster for me than 700MB did. Broadband is here to stay and is only getting faster. The average computer, its display adapter, is getting faster and can display higher bitrate video content. Filesize is only going up.
Evolution
I feel that DVD-R is a clear improvement on technology compared to CD-R. There are a number of practical issues to consider. It looks like they did their homework and fixed the main issues with CD-R.
Number one is sandwiching the recording layer between protective plastic discs, as opposed to putting it on top, as CD-R did, where it is easily damageable.
The other is the overall improvement of recording reliability. Granted I only use high-quality media, but it seems to me that either thru improved error-correction algorithms and/or improved quality control/design of both recorder and media, DVD-R far surpasses CD-R in reliability. I haven't burnt one single bad disc that was directly related to media or recorder in over 1000 burns on multiple recorders. CD-Rs would often fail to verify.
Price
There is no contest as far as the price, per GB, of DVD-R vs. hard drive for backup purposes. Believe it or not, backup media has traditionally been lagging behind the real needs of customers.
Standards
CD-R had no competing standards. Good. In the beginning of DVD-R, it was a problem if you had a -R and someone else had a +R. Bad. They fixed it by having virtually all drive manufacturers, for both recorders and readers, seamlessly support both standards. Fair enough, and it gets a "fair -to- good" grade. It is transparent enough that today you don't need to even look at what media you're buying (if your name is "John Smith," of course - us freaks look at much more than just the brand of media we buy). But DVD-R was clearly a step into the general direction of chaos as compared to CD-R. It looks like the next gen will be considerably worse, unless one of the standards completely kills the other one before either comes to market.
Conclusion
Please note that I am not closely following the BR vs. HD-DVD race because I think it would be a waste of time at this point. This is a disclaimer for any specifics I mention - they are only approximations.
I feel that 100GB should not be viewed as realistic. 4 layers are not practical unless they are introduced from the get-go. I offer current DVD-R dual-layer as an example. It has 2 major cons: 1) it is currently roughly 10-30 times as expensive as single layer DVD-R for roughly double capacity, 2) it does not burn anywhere near the speed at which DVD-R SL burns (fastest is 4x vs. 16x, realistic is 2.4x vs. 12x). The only people who spring for it are the ones that use them for video backups. Being that I only back up data, it would be of no use to me even if one of the two above points were to go away.
Therefore, lets say a single layer disc will have 25GB. Nothing wrong with that, but by the time it is introduced it will be "just enough" to satisfy the needs of the market.
I feel that backups will still be lagging for a while into the future. Don't believe the hype, and don't feed the trolls.