Thanks for the detailed explanation. Seems like setting up a proper NAS of photo library can be quite complex.
Think i will 1st try and experiment with Time Machine backup of my photos stored in the external HDD connected to my Macbook. Will be good if such a config is possible for cos
1. The whole OS, registry, doc files and photos are backed up in Time Machine
- either time machine or my ext HDD fail, i won't lose my photos
2. Regular Autoupdating
3. Lower cost - buy ext HDD only, my Airport Extreme is on 24/7 anyway
btw how is time machine not suitable for photos?
If you are using NAS, I wouldn't recommend you use iPhoto. Try using Adobe Lightroom or similar Photos Management software which can just treat each photos as-is and they managed by cataloging where you can tag the photos and perform processing at the same time. Because they store the catalogue pertaining to the software and not mixed with the photos, it makes it easier to store the photos elsewhere. Time machine can also be configured on NAS such as Synology, which is what I used, so you get network accessed Time Machine for your system and also file based storage of your photos.
Time Machine makes it easy for you to restore your system, but what time machine sell is not the restore part. Time machine sells incremental backup. When you add photo, incremental comes in as extra storage, which is the same as adding new photos into a storage, but of course, you get the extra tagging in Time machine on when they are added. But the benefits in this is minimal. Time machine promises you can revert to any time line in the past for each specific document or items based not the implementation of the application. When you restore your system, you don't need to restore back all the photos. As long as you know they are safely somewhere, it's good enough.
Cost is relevant to durability, so if you want it cheap, it doesn't come safe. That's all I have to say, you decide
Time Machine in my opinion is not suitable for photos generally is based on my understanding of deduplication process. It comes in file based and block base. Should Time Machine operates in file base, then each time you change a photo, it's a complete file upload into the time machine which is costly in time and space. You change 10 times your photo, you end up with 10 times the size of each iteration of the same photo stored. Meaning it's no difference in terms of space wise versus you store each photo differently with different filenames. But of course, you normally wouldn't. Should it be operating in block based, you will find for JPEG that is what normally users use, a bit of change in one area of the photo has so much effect on the binary representation of the file which is spread across the whole file. Effectively if you just change 5% of the photo, you end up having probably 50% of the photo looking different from the perspective of binary representation. Time machine deduplication is not going to perform full length analysis of diff to comes up with the smallest changes. Such technique are computational intensive and will be too taxing on a consumer system. You end up almost halve the file uploaded, should it operates in block-based deduplication. This is the basis on my argument that Time Machine makes bad deduplication system for images.
On the other hand, text documents, or text markup documents such as Word, Powerpoint, or other relevant documents makes good candidate for Time Machine because their changes are localize. You change the title of the document, it wouldn't effect the same binary for all other 999 pages in the same document, which makes deduplication very effective in space and time.
You can go try with Time Machine. I used it too on my external firewire hard disk and also have tried over the network to my NAS. It is slow when you have large changes. I don't store my photos in the very same computer I use, I store them in my NAS which I can access them everywhere in the world, because it's externally accessible over the ISP's fibre network
