Same source, two Macs. Ideas?

[Selwin]

My friend wants to jump ship from aperture. His source files are on a synology network share. He has two macs both with LR 6 / CC installed. One Mac (iMac) has the master catalog, containing all of his life's work. The other Mac is a laptop containing a smaller catalog, used for photo shoots in the field that require immediate editing.
He wants to minimise sync efforts. The plan is to write changes to XML files, copy the source files over from macbook to synology and import from the iMac, using the XML files to transfer edits to the iMac catalog. So far so good. However, XML files will be changed by one computer's catalog and read by the other so he will get the inevitable exclamation marks at some point when he starts to work on the same files from both computers.
This will require user action no matter how we twist things. Or will it?

Other options we've discussed
Using EHD is not a viable option. Using Dropbox to sync the catalog also requires user sync efforts. Also, he wants to be able to use LR on Mac B while LR is also still running on Mac A (too lazy to take the stairs to shut the other one down). This would obviously at least require all XML operations to be performed on the fly and not until LR shutdown.
Using "export as catalog" is my preferred method but obviously has conflicts with this user's requirements.

i am open to any ideas to help this user along. He is familiar with scripting (but LR appears not to support apple script) and he knows his way around SQLite.

Thanks in advance!

 

[Roelof Moorlag]

These requirements are too much i believe. The option with dropbox is the most easy way, almost with no effort. What are you refering to with "Using Dropbox to sync the catalog also requires user sync efforts" ?

 

[johnbeardy]

I'm pretty sure that with Aperture he wouldn't have been able to do what he now wants to do. It also had to be on a local drive (same underlying database) and it couldn't even save adjustments to xmp files. So that alone would be a step forward. He's going to have to learn to save and read metadata. Personally, I think he should do it manually - imagine the risks of one catalogue automatically overwriting xmp files written by another.

And keep him away from SQLite. Users never need it.

 

[Selwin]

Ok thanks guys, good input so far. He's not saying he could do all he wants with aperture and not bashing LR either, just exploring possibilities.

I am envisioning now doing it myself, as a thought experiment. I too have two computers and I've thought the same thoughts but always preferred the safety of using one catalog on one machine.

So for arguments sake....
I suppose the preferred Dropbox route would be to put the catalog in Dropbox. Immediate problem is that the previews will grow way too big for my Dropbox to hold (my current previews file is over 90gigs) and more importantly, syncing will be painfully slow. I don't need the previews synced anyway, I can live with two separate sets of previews on each computer I use this catalog. But I can't find a way to disable syncing only the previews.

Additionally, what if I started working on some images on my laptop and leave it running in the kitchen while I walk upstairs to the attic to work on my desktop computer. If I open the same catalog (in Dropbox) on the second computer things are bound to go terribly wrong as the laptop still accesses the same file. And even if I promise myself to carefully always shut down LR on each machine before moving to the other (and wait for Dropbox to sync), there will inevitably come a day that I do forget and then what?

I'm used to using the "export folder to catalog" route as it is safe and straightforward. Surely there are a massive number of users that face the same challenge at some point? What do they do?

 

[Johan Elzenga]

Synching should not be that slow. The 'previews.lrdata' may look like one huge file, but it isn't. It's a so-called 'package'. A package is a folder that looks like a file in the Finder. When synched, only those previews that are new or changed will be copied, not the entire package. So after the initial sync, updates will go much faster. You will need a paid Dropbox account however, because of the size of the previews package.

 

[Selwin]

Thanks Johan. Yes I know about the package files in OS X, that is not an issue you are right. I meant there will be many megabytes to sync after some serious 100% previews creation, or even after creating 2000 standard sized previews. Let alone the trouble of stopping Dropbox sync while on the go and using my phone as tethered Internet to fetch some email.

And personally I don't need or spend money on a pro Dropbox account.

 

[tspear]

Since you have a Mac, you can create a symbolic link in the catalog folder called previews.lrdata which points to another area on the disk.
Dropbox will not follow the link, but Lr will.

I also think Dropbox is too expensive. Google Drive and Microsoft OneDrive for this purpose work the same way and are much cheaper.

As for what happens, you get a collision. And the default behavior of each sync software is to keep both. So you end up with two catalog files, no data corruption though. Then it is a matter of making sure you pick the correct file, delete the other one and redo the work you just lost (or export the few images as a catalog and import it back into the master)

 

[Johan Elzenga]

Since you have a Mac, you can create a symbolic link in the catalog folder called previews.lrdata which points to another area on the disk.
Dropbox will not follow the link, but Lr will.

Unfortunately, that is not true. Dropbox will follow that link. So even though you will only see a symlink in your local Dropbox folder, the entire package will be synced to the Dropbox servers. I use this to make cloud backups of all my user folders (I do have a pro account).

 

[tspear]

Johan,

Then Dropbox made a change. I used to use that feature so I could keep the catalog on there. Oh well.

 

[Selwin]

Synching should not be that slow. The 'previews.lrdata' may look like one huge file, but it isn't. It's a so-called 'package'.

Even of this were workable (it might be but a 1GB catalog will take ages to sync to/from Dropbox, even without the previews), the solution does not meet the requirement of working on the same set of source images from two different computers (alternately, not simultaneously).

In theory, the thought of using XMP files to write the edits into and reading them from another catalog is not so bad. However, to make this theory work, we would need Lightroom to not write the edits inside the catalog as well. As far as I know, this is not a selectable option so the plan will fail whatsoever.

I think the best thing I can advise him is to move files (with their edits) through the "export folder as catalog" command from the MacBook catalog to the iMac catalog and be done with it. If he chooses to use the XMP files he could theoretically import any set of images into a temp catalog and apply the edits. Then, after working on the images, export them back as a catalog and LR should apply the changes to the catalog. In theory, there shouldn't be any conflicts after the import. I may try this out on a dummy catalog myself.

 

[Johan Elzenga]

Johan,

Then Dropbox made a change. I used to use that feature so I could keep the catalog on there. Oh well.

It's been like this for as long as I use Dropbox, and that is a long time. I doubt this is a change in Dropbox, because I doubt you can make an application (not) follow a symlink. A symlink works at the OS level, so any application that uses the OS to locate files and folder will automatically follow a symlink, whether you like it or not.

 

[tspear]

It's been like this for as long as I use Dropbox, and that is a long time. I doubt this is a change in Dropbox, because I doubt you can make an application (not) follow a symlink. A symlink works at the OS level, so any application that uses the OS to locate files and folder will automatically follow a symlink, whether you like it or not.

Following or not following a sym link is very easy. It all depends on how you open the file handle.
Here are some details: symlink(7) - Linux manual page

 

[Johan Elzenga]

Following or not following a sym link is very easy. It all depends on how you open the file handle.
Here are some details: symlink(7) - Linux manual page

OK, although MacOS is not Linux, I suppose it applies to MacOS too. In any case, Dropbox does follow symlinks, so the suggestion that pops up from time to time to place the Lightroom catalog folder in Dropbox and move the previews out of the catalog folder and use a symlink do not work.