- This topic is empty.
A Dreadful Warning
-
Actually
Prime brand DVD-r have a shelf life of around 100 years through accelrated test results
I have DVD-rs running 24/7 in museums that have been running for 8 -10 years without failure
heres a quick link to just one of many information sites
Odd… I worked with a guy whose son worked for CERN. They used to archive data onto CD but found they were losing it after 3 years. My own experience is that CD’s I’ve burned also only last a few years.
There are factors which help etc
how they are burnt – burn faster – more errors, more crc corrections the drive has to do, so then scratches and corrosion make it worse. I never burn dvds at morethan one speed, it reduces the ammount of errors on the disc hugely
how they are stored, most CD cases are really not the best place to store discs, the soft cases with protective inners are best – make ahuge difference to the ammount of scratches on the surface
major temperature changes affect DVDs in particular as they are 2 pieces of plastic glued together – CDs are one single injection moulded piece
the brand of discs, some of the better brands have much better oxide coatings with a much longer lifespan
how much they are use and what in
Optical discs are actually quite robust, i have somethat have been burnt over 10 years ago – pre-masters of audio recordings and they will happily play still
Phil wrote:
Has anyone got their hands on a blue ray drive yet?
Lacie do one for about 1,000.00 euros, the single layer discs hold 25gb and a dual layer disc holds 50 gb of info. the discs are about 25 euros each!
Not very often I need discs of that size but occassionally a job goes out on 3 or 4 dvds, think I will wait until the price drops a wee bit.
Personally I will stick to backups on both disc and harddrive, the hard drive for easy access and in the event of failure go to the correctly labelled box containing several hundred discs and dig out the one needed!!
As some of the others have suggested, the best solution overall is probably a combination of various methods.
Here’s what I do :
(1) Back up to an external disk drive using the free SyncToy utility.
(2) Back that disk to a second disk drive using a separate set of SyncToy parameters (keep this one in a different location).
I don’t erase my memory cards until I have at least two other copies.(Incidentally, disk drives came from Sheldon originally).
(3) For the Raw files only, I’ve now started backing up to an online site using the Amazon S3 service (the cheapest for what it provides).
http://www.jungledisk.com/index.shtml is the actual utility I use for this this.
I’ve also looked at http://mozy.com/Very safe – only downside is the very slow broadband upload speed, so I batch them up into overnight loads until I’ve caught up.
(4) Last, but not least I back up to high-quality DVDs bought for this purpose from
http://svp.co.uk/So, a bit of hassle to do, but I think it’s worth it.
Just add even more to your paranoia.
Have any of you considered the case where files on your computer get corrupted and you then unknowingly proceed to backup the corrupt files over the top of the good backup files?
This has got me worried recently after a couple of nasty hard drive clatters. As there is no way to check for corrupt files other than by opening every one, I am paranoid that I might be overwriting good data with corrupt data.
To protect myself I am now doing my daily incremental backup to an external disk AND a six monthly master backup which never gets overwritten.
Something to think about.
Andy
a common backup strategy is to use:
4 backups which are recycled (mon, tues,weds,thurs)
4 that are used every friday (fri 1 used week one, fri2 used week two etc)
1 which is used each month (never overwritten)
this way you have 4 weeks worth of backups using just 8 backups, then 12 for the year to give you a years worth aswell
I can speak from experience of using hard drives recently
I archive projects to a hard drive (new hard drive for every project). and use a pair of mirrored drives for current work. a couple of month ago both of my mirrored drives failed at the same time (whats the chances) I lost 3 months worth of work basically (had some of it on my NAS etc )
You must be logged in to reply to this topic.
