My hubby suggested yearly DVDs (however many it takes each year). I'm seriously considering going down that route. My only concern was that if DVDs became obsolete, how would I get access to my images... but hubby said that if DVDs were no longer sold then we copy them to the latest storage format.
Having said that, my 2tb external drive is smaller than a few DVDs, but its a way of backing up my photos without having to use the cloud
1. I have found that DVD do not last long. I have some which are 7 years old and the data can only be read after a lot of tries (I have verified it on a brand new drive). So I have stopped using DVD.
2. DVD = 4.7GB, 1TB = 1000GB = 212 DVD. Add wasted space due to file system and large file granularity and you can safely assume 225 DVD/TB, so 2TB ~ 450 DVD, a daunting task to write and verify them. By the way even I have over 500 DVD of archived data in 6 large boxes. A 2TB disk will occupy a fraction of that space, be more accessible and data faster to retrieve.
3. A 2TB HDD is much cheaper than 400+ DVD. Just use a slow - 5400 RPM drive for archiving, they are more reliable than the faster drives. Both Seagate and WD have slower drives meant for archiving.
Here is what I do at present :
. I have 3 external USB drives - 1TB, 750 MB and 500MB.
. I regularly copy all the relevant data to these disks, so I have 3 copies on external media.
. I have quite a few 160GB, 300GB and 750GB internal HDD. I have copied two sets of very old data to these disks. I have a hot plug cage on my desktop, so once every six months I just check the data - write to a scratch disk and then write it back to the data disk. This ensures that the data is not only correct, but refreshes the disk surface.
I future I am planning to acquire a series of 1TB or 2TB external USB3 drives and store all my data in duplicate on them.