Sync LR Catalog between 2 computers but not master files

[gb3arts]

I have LR5 on my main iMac desktop system and on my Macbook Air.

The iMac is connected to a disk array which stores my master photo files.

I would like to sync this catalog (iMac master) with the Macbook Air and only be looking at previews on the Air,

so that I can choose selects on the road.

I would come back to the iMac to work with the master files.

Is this possible and easy? I'm not interested in having my files live in a cloud or cloud based sharing or anything like that.

Just Catalog with previews on the Air which sync to Catalog on the iMac.

Thank you,

Greg

[Michael J. Hoffman]

It all depends on what you mean by "sync." If you aren't going to use the cloud, how would you sync the two machines?

Here are some ideas:

1. You can copy the catalog and previews from the iMac to the Air, and open that catalog on the air and you'll be in business.

2. If you have Smart Previews for all the images, you would be able to use the Develop Module as well, and make adjustments to your images while on the go.

3. When you return, you'd need to overwrite the iMac catalog with the Air catalog so that you have any updates you've made.

4. If you take a copy away on the Air and make changes, then come back and make changes on the iMac before you copy over from the Air, you've created a conflict and your process will be broken.

If, just for the sake of comparison, the catalog and previews were on DropBox or Creative Cloud or somewhere like that, the copying would be automatic (as long as you waited for the updates before opening Lightroom on the other computer).

Victoria Bampton's book Lightroom 5 - the Missing FAQ has some sections devoted to a multi computer workflow. It's an excellent Lightroom book all around as well.

mh++

[phillydave · Accepted solution]

My new workflow involves my Mac and MacBook Pro, as well. Expanding on what Michael said, I put my working catalog on my DropBox folder that I synchronize between my two computers. I'll load my images on my Mac and generate smart previews. When I load that catalog from DropBox on my MacBook, I get the smart previews with the catalog so I can pick, keyword, and even post process. When I go back to my Mac where the original images are, I can open up Lightroom, see all my edits and such, and then finish up and export my processed images.

Any synchronizing technology (DropBox, CC, Google Drive, custom solution) will work. You basically just want that catalog to be sychronized between multiple computers. It's magic. The only caveat is that if you're fast switching between the two computers and both machines are trying to edit, you'll get conflicts. But my workflow rarely does that, and I just make sure DropBox finishes its deal on one computer before I open Lightroom on the other.

[gb3arts]

This workflow concept sounds perfect.

Few questions if you don't mind.

1. Are the previews, be they smart previewws or just standard, contained within the catalog or is there another folder / files set I need to post on dropbox with the catalog?

2. With this workflow I am assuming my catalog will now only exist on dropbox. Maybe I set backups to be on master iMac.

     Will this slow LR down - having to read from dropbox?

     Not doing any fast switching - is really just to be able to make selects when not at my studiuo and iMac.

3. Having not done this before, is there anything I need to be aware owhen moving the catalog to dropbox?

     LR is cool to use dropbox for catalog or do I need a plug in?

Thank you very much,

Greg

[phillydave]

1. LR will create the preview and smart preview files alongside your catalog. I think you can change that in setting somewhere, but I believe Adobe says not to. So in my DropBox folder for Lightroom, I have my catalog (.lrcat), Previews.lrdata and Smart Previews.lrdata. But LR manages all that for me, and DropBox does all the synchronizing.

2. From your computer's perspective, the DropBox folder is just another folder. The synchrozing all happens over the magic of the internet, but once everything is updated, its just local files on your local computer, so the speed and such depends on what drive you put it on.

Re: fast switching. Those previews and catalog files, at least on the Mac, are actually bundles of stuff. So when you make changes in Lightroom, dropbox has to process all that and send the updates back to the cloud. It can take a few minutes for a few changes, or if you import a huge catalog of stuff, that synchronizing can take more time. My point on that was just to make sure that DropBox had finished sending the changes to the cloud from your one computer and that DropBox has updated the changes on your second computer before you open up LR on the second computer and try to make changes. You'll wind up with "conflict" files on DropBox. It's not the end of the world, just a pain, so just make sure DropBox has done it's job before you try to make double edits on the same catalog on two different computers.

That said, if you let DropBox do it's think, you can (and I have) completely processed (keyword, select, and post process/develop) projects entirely using smart previews on my laptop, then just gone back to my desktop to export. The beauty of smart previews is that you can do all of that without having access to the original image files, which for me are only located on my desktop. It's magic.

3. I'd leave the catalog where it is and either make a new copy of it, or export your stuff to a new catalog in a drop box folder. Worst-case scenario, your existing catalog is still intact. Backups are always your friend. Also, just be aware of the siz of your catalog. I have a working catalog on DropBox for active or recently active projects. That keeps the total file size down because you don't get a ton of space with the free account. Once I'm done with a project, I can export it to a static catalog on my desktop and network drive for archiving. Google Drive gives you more space but I personally don't need to carry my entire catalog around, but something to think about.

Again, LR doesn't know you are using DropBox. It's just a folder locally on your computer.

Hope that helps!

[Michael J. Hoffman]

I'd add only two points, to clarify and to warn:

1. lightroomfanatic advocates putting the working catalog in the Dropbox folder, which is a very good solution. This does mean that the previews and smart previews folders (which have the same name as the catalog, with "Previews" or "Smart Previews" appended) will also be located in the Dropbox folder. Keep in mind that the previews folders can grow quite large, so be aware and make sure you have enough storage available in Dropbox to cover it.

2. If you fire up Lightroom on both machines without letting Dropbox sync first every time, you could end up with a conflicted version of the catalog and previews. For example, you use the laptop while traveling, but don't have time to let dropbox sync when you get home. Then, you fire up the home system and use LR as well. Now the two have completely different versions of the catalog and Dropbox will not know which one is correct (neither one will). Dropbox cannot merge two sets of changes together, it's important to allow the sync to complete before using LR again on the other machine.

mh++

[areohbee]

If I were using DropBox for this, I'd exclude the previews by moving them to a different disk. Otherwise you have multiple gigabytes of extraneous stuff to sync...

You can do this manually (by making links) or let PreviewExporter do it for you.

[phillydave]

I'm too cheap to upgrade to DropBox pro, so that's why I only use it for a working catalog and not my entire collection of images.

I also:

1. Remove smart previews when I'm done with them to free up space.

2. If my regular previews file gets too big (I move images in and out/archive regularly), I'll clean up my previews file, too.

That's an interesting idea about having the other previews stuff on a different disk. So each computer maintains it's own non-dropbox version of a preview file? Can LR generate previews on my laptop without having access to the original images? I thought it needed the originals?

[areohbee]

lightroomfanatic wrote:

That's an interesting idea about having the other previews stuff on a different disk.

Works perfectly, and is a tad faster than having them on same disk as all the other stuff..

lightroomfanatic wrote:

Can LR generate previews on my laptop without having access to the original images? I thought it needed the originals?

It needs originals OR smart previews.

~R.

[phillydave]

Cool, thanks!

[gb3arts]

Great discussion.

I very much appreciate the input and am excited to implement it.

Good notes on the sync and potential conflict files.

I like the concept of having the previews/smart previews on dropbox - I pay for my account so I have 100 GB.

My concern is that every time I change folders within my catalog, LR is going to have to go to dropbox to get the previews.

I currently have them on a thunderbolt disk array and that takes a bit to move from one folder to another.

[areohbee]

gb3arts wrote:

I like the concept of having the previews/smart previews on dropbox

Indeed - nice conceptually, but the reality of it? It's one thing to have smart previews on dropbox (which don't change once they're created), and another thing to have regular previews on dropbox, which are constantly changing. I mean, whatever floats your boat and all, but if it were me I'd keep regular previews local, if possible, regardless of your account alottment... My catalog is like 1.5 G and my previews are many multiple Gs - it takes a long time to sync multiple Gs over the internet. Put another way, it's not the storage but the transfer time that makes the issue. I mean, I'd be curious to hear the results of your trial (I've never tried it) - if you're not updating regular previews much, and/or don't mind the lengthy sync-before-use, it may be just fine...

[phillydave]

Remember there is no "going to dropbox". Behind the scenes, DropBox does the updating and so its a local file once all the syncing is done. But if you are on a computer working locally and locally Lightroom needs to generate previews, it needs to generate previews whether you are using DropBox or not. But it's doing it locally as far as your computer is concerned, again, whether you are using DropBox or not. It's just that if you are using DropBox, those changes are copied to the cloud and then can be synchronized with a remote computer, too.

My LR folder is 500MB. Like I said, I don't keep my entire catalog on DropBox, just my working stuff so having the catalog and 2 preview files in the same folder synchronized with DropBox works great for me, though I'll explore some of Rob's ideas, too.

[ckautz]

Just began this process w/new MacBook Pro. My question is when DropBox is syncing my data for use on the desktop after edits on the laptop, does it have to upload/download the entire catalog? We have severe restrictions on broadband usage and my catalog is 1.5 gb so would eat up our 15 gb/month limit in short order. I plan to only put catalog on DB, previews or smart previews on each of the machines.

[ManiacJoe]

Yes, the entire catalog file needs to be sync-ed.

Many people have found that using a LR catalog directly from the DropBox sync directory to cause problems. Each time you want to use the catalog, you may need to:

- let DropBox sync the catalog file down to your computer.

- copy the catalog out of the DropBox folder to an "in use" folder (that also stores your previews).

- open lightroom on the "in use" catalog. Then close LR when you are done.

- copy the "in use" catalog file to the DropBox folder.

- Let DB sync the catalog up to the cloud.

To save bandwidth, you can ZIP the catalog before copying it to the DropBox folder.

[sirpete]

There is no need for in use folder, if you allow syncs to finnish before opening catalog. This is because LR will also make a lock-file beside the catalog.

But still it is possible to cause Dropbox conflict. In the case there happens to be changes made on two machines simultanously (without a complete sync in between) the conflict is detected by Dropbox and causes a conflicted copy file to be generated [1]. In this case the conflict must be manually merged to the libraries by copying conflict out from Dropbox and using Lightroom to open, identify change and merge manually the changed parts.

Depending on user preference and behaviour the separate folder copy may still be better. I am not sure which slot I fall into. So far I have managed without dropbox external folder.

The issue with preview files is discussed earlier in this thread.

[1] What's a conflicted copy? (Dropbox Help Center)

[ckautz]

Thank you for all this info. I'll read all & see what I can glean. I'm a photographer and heavy computer user, but not a tech!

[Mosco_F]

Just for completeness: the previews file appears as a single file but it's actually a package of thousands of files (depending how many pictures you have). Therefore, it will sync the previews one by one as they are added/modified, not the whole package.

This is why I have decided to also sync all my previews as I have a Dropbox upgraded account.

[jcvddoel]

Yes, the entire catalog should be synced ... with a slow (or expensive) connection you should also enable LAN sync in the Dropbox settings which would make the sync between local computers less dependent on your broadband usage.

[sirpete]

This is slightly more complicated.

Dropbox supports partial file updates [1], so it is possible to update just the changed parts of the Adobe Lightroom catalog file. However there is another point here.

Lightroom catalog file actually contains a SQLite3 database [2]. SQLite3 database, like most RDBMS [3] have the tendency to write all over the file causing little changes all over. Thus making partial updates and differential updates less effective. So it depends, but you will not be pushing the whole catalog all the time, only the delta. However the delta may sometimes be large.

[1] Does Dropbox always upload/download the entire file any time a change is made? (Dropbox Help Center)

[2] Jeffrey Friedl's Blog » Accessing Lightroom’s SQLite DB Directly

[3] Relational database management system - Wikipedia, the free encyclopedia

-Pete

[sirpete]

Oh, and making a zip file might well make the delta larger.

-Pete

[Michael J. Hoffman]

I like the idea of having the previews in a separate (non-synced) folder, but I'd want the smart previews on Dropbox (assuming the second computer is a laptop and you don't want to drag the full catalog on the road.

Lightroom will create new previews from the originals or from smart previews pretty much on-demand, so I don't see too much of an opportunity for conflict. I don't know much about the details of LR's preview organization, but I'm assuming that having two different sets of preview folders for the two machines wouldn't create any conflicts (like accessing the wrong preview or deciding that the previews are corrupt).

I'm going to experiment with this!

As a side note, I keep my LR presets, templates and preferences in a linked folder on Dropbox also. This allows me to sync settings between machines and to recover settings if I have to reinstall or migrate to a new machine.

I accomplish this also by creating a symbolic link from the Lightroom preferences parent folder to the Dropbox Lightroom folder.

mh++

[Brian of SummaeStudios]

What can/does one do if one does have a 'conflicted version'? Lightroom will no longer open on my laptop at the moment. No biggie, still experimenting, but I had thought I'd closed the app and let CC sync, and this still occurred. Any solution, or do I delete the catalog, start again, and be more careful?

[Brian of SummaeStudios]

Still having problems sharing one catalog between my laptop and desktop using Creative Cloud, as opposed to Dropbox, and smart previews. Though I made darn sure the catalog folder in the CC folder was fully uploaded by my desktop and lightroom was then closed. Still though that catalog opened fine the first time, when I closed it and LR was backing up, something broke and I can now, for a second time, not access a catalog on my laptop...

Any advice on what might be going wrong?

[julialloyds45]

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