Thanks for the specific suggestions. If I may - I have a few 'clarifying questions'...
does that library need to be accessible from only a single account (the photo uploading act, as it were) to ensure it cannot be concurrently accessed (e.g. if someone had left A3 open and not logged out and then someone else opened it on their account...that'd be 'concurrent' access to the library, correct?
Andy,
Libraries are really "happiest" when they are private to one account/user. They are not really meant to be shared.
Personally... even if libraries supported multiple user concurrent access (they don't)... I still would not want someone else mucking around with my library.
It is a
personal workspace... where you can create fantastic projects.
This will perhaps make more sense after I've spent some time with A3, but 'transferring projects' from multiple other machines/acts into that master which lives on the imac is 'safe'...because project transfer is an atomic action? or because you 'pull' from the act/machine that owns the master so it's only open in one place?
The basic building block of A3 is a "project". When you import pictures into A3, that "original" (previously called master) lives in a single project... and only one single project. From the original, you can have as many "versions" as you desire. They can be used anywhere... so you are not restricted to having just the originals. You can create versions for different uses, that look different from one another. They still derive from the same "original".
One of the options that you have is to migrate projects from one machine to another. When you do that... all of the information about the photo transfers. The two commands that are used is "export project as a new library". Later you can merge that library back into your main library.
This becomes useful if you want to take some work with you on a trip and work with it. If you export a project, then you can do anything you want on that project, and then when you come home, you can merge that project back into your library. You do not have to take you whole library with you.. you can just take individual projects.
Likewise... on a trip you may create a new project. During a two week B&B tour around Ireland, I created a new project "Ireland" on my MBA. Every night I would import pictures from both of our cameras. I could rate them, sort them, manage stacks, keyword, etc. That project grew every day, and I did the incremental work that adds significant value. When I returned home... I merged that project back into my main A3 library... and it was no different than if I created it on the iMac from inception.
If you want to think of it as an Atomic operation... then that is fine. A3 is designed to import projects into the master library... or merge projects with different versions of that project... and it protects all the data. This is similar in idea, (but not operation) how a memory or storage operation would operate with atomic primitives.
and the copies are read only? That is, no sorting, editing, face identification, etc happens on them because changes won't be pulled back into the master library?
They are external to your library... using whatever program, or structure you wish. I know you are hanging onto the concept that others want "everything". I believe that by doing so, you are diluting the real value of what is possible. Most good photographers that I know spend a lot of time culling their collection to something that is much smaller... and MUCH more valuable than having all of the great and crap shots all mixed up together.
I have toyed with the idea of using CCC or similar program to do a one-way sync of my database to my wife's account. This would give her everything at her disposal. However, instead I create fantasic collections of our work that have purpose, focus, and organization... all of which gives her use of our photo collection that far exceeds the value of a big blob of crappy photos.
If she truly needs everything, then just import everything into each of your own A3 libraries.
One final suggestion, that will far exceed the value of everything you have read here... go to photo.rwboyer.com and buy his extremely inexpensive eBooks. In particular, get the "organization" and "file management" books. I predict that you will read them at least 20 times... and things will become clear.
BTW: I do wish that A3 or LR supported better sharing... in a safe way... and in a way where one person's work did not affect another's. However, it just does not work that way. In the end... I am not 100% that it should.
/Jim