Share one Adobe LightroomCatalog between multiple Computers

Introduction

As most of you are aware, the AdobeLightroom Catalog is not meant to be shared between multiple computers or beinglocated on a network drive. For many photographers this behavior is veryunpractical and unwanted as it is common to use laptops while abroad or onphoto shoots and desktop computers once back home. You can of course import andexport catalogs but I like to have the same catalog with all my photos on my laptopand on my desktop computer.

The following article describes how I setup and synchronize my Lightroom catalog across multiple computers and whatcaveats to be aware of.

My Setup

My setup consists of one Apple iMac and oneApple MacBook Pro. As a NAS I use the Synology Diskstation DS713+. The LANinfrastructure is based on Gigabit Ethernet and 802.11ac Access Points. I havenot tried if this solution also works in a Windows environment (eg. useShortcuts instead of Symbolic links) or with cloud services such as Dropbox in theory it should though.

The following picture shows my currentsetup of these two computers sharing one Lightroom catalog but it can easily beexpanded to more than just two computers. All photos are located on a networkdrive provided by my Synology NAS. While the desktop computer can always accessmy photos on my NAS the laptop is often being used abroad without access to myphotos. This problem off missing original photos is solved by generating SmartPreviews on my laptop computer for all my photos. I do not use Smart Previewson my desktop computer.

[PHOTO label="Topology.png" id="957" media_type="image" link="none" album="62" caption="both"]

 

 

ConceptDescription

 

Lightroom Catalog

 

The general idea is to place the Lightroomcatalog file on a local directory that is being controlled/monitored by a cloudservice such a Dropbox or as in my case the Synology Cloud Station Service.Lightroom allows to specify the location of the catalog file as long as it issomewhere on a local hard disk drive.

 

I do run my own Cloud Sync Service on aSynology NAS as I don't want private and sensitive data to be replicated toservers that can be accessed by third parties. An equally important reason forusing the Synonolgy Cloud Sync Service is the synchronization speed due to itslocation on my LAN. The Lightroom Catalog can easily be multiple gigabytes insize and will be synchronized every time it changes, eg. when I close Lightroomeither on the laptop or desktop computer.

 

 

Previews

 

In Lightroom it is not possible to specifythe storage location of rendered previews and will always be collocated withthe catalog file. Depending on your preferences, all rendered previews combinedwill be very big in size - in my case way over 30 GB and I do not want to synchthem every time some preview information is added or changed. As the Lightroomcatalog is located in a cloud sync directory, also all previews (one containerfile) would be automatically synced. The easiest way to circumvent thisbehavior is to create a symbolic link (alias) of your Previews next to the catalogfile which points to the actual location of your Previews container (outsidethe directory used by the Cloud Sync Service) on your hard disk. This way onlythe symbolic link will be synchronized to your cloud service while the actualpreview data remains on your local hard disk.

 

 

Smart Previews

 

First a quick recap of Smart Previews:Smart Previews are smaller versions (in size and dimensions) of your originalphotos (in my case mainly DNGs or RAWs) that will be used by Ligthroom incase the original files are not accessible. Lightroom allows you to domodifications and adjustments on Smart Previews the same way as you could dowith your original photos. Of course, printing and exporting should only bedone while the original photos are accessible.

 

As I do not keep my original photos on alocal or directly attached hard disk but rather have them on a network share,Lightroom becomes more or less useless if it cannot access the source files.This is not an issue for the desktop computer as it will always have access tothe network drive that contains my photos. For my laptop, which is often used outsidemy LAN, it is a problem though. The simple solution is to generate Smart Previewson the Lightroom instance installed on my laptop. Currently I have about 50000photos in my Lightroom catalog and the Smart Previews for these 50k photos addup to roughly 60 GB not too much space by todays hard disk sizes.

 

The location of the Smart Preview containercan also not be user defined and like Previews is colocated with the catalogfile. So like for Previews, also Smart Previews are not physically locatedwithin the Cloud Sync directory but on a different location on my hard disk andonly the symbolic link to this container file is being synchronized.

 

 

Folder Structure

 

The following picture shows my Cloud Syncdirectory (Users/Marco/CloudStation/Lightroom/) that contains the physical Lightroom catalog (LightroomDatabase-5-2.lrcat) and the sybolic links to thephysical Previews and Smart Previews container files (LightroomDatabase-5-2 Previews.lrdata and LightroomDatabase-5-2 Smart Previews.lrdata). Thefilenames being italicized indicate that these two files are symbolic links (Iuse a tool called Path Finder instead of the terrible macOS Finder whichApple should be ashamed of!).

 

(Ignore the LR Plugins and Print Templatesfolder!)

 

[PHOTO label="logical-catalog.png" id="955" media_type="image" link="none" album="62" caption="both"]

 

The two Symbolic-Links above point to these physical container files:

 

[PHOTO label="physical-catalog.png" id="956" media_type="image" link="none" album="62" caption="both"]

 

 

Setup Folders and SymbolicLinks

 

So how would you setup all of the above?Here are the simple steps:

 

1.    Make sure Lightroom is not running

 

2.    Make sure you have a backup of your Lightroom catalog!

 

3.    Move (or copy) your Lightroom Catalog file to your Cloud Syncdirectory. In my case this is:

/Users/Marco/CloudStation/Lightroom/LightroomDatabase-5-2.lrcat

 

4.    You can leave your Previews and Smart Previews at their currentlocation. In my case this is:

/Users/Marco/Documents/Adobe/LightroomDB/LightroomDatabase-5-2 Previews.lrdata

/Users/Marco/Documents/Adobe/LightroomDB/LightroomDatabase-5-2 Smart Previews.lrdata

 

5.    In your Cloud Sync directory create two symbolic links pointing tothe physical location of your Preview and Smart Preview containers

 

a.    Open the Terminal

b.    Change (cd) to your Cloud Sync directory

            cd /Users/Marco/CloudStation/Lightroom

c.    Create the two symbolic links to the physical Previewcontainer files

            ln -s Users/Marco/Documents/Adobe/LightroomDB/LightroomDatabase-5-2 Previews.lrdata

            ln -s Users/Marco/Documents/Adobe/LightroomDB/LightroomDatabase-5-2 Smart Previews.lrdata

 

6.    Start Lightroom and open the Catalog located in your Cloud Syncdirectory (File > Open)  

 

 

Caveats

 

I am using this setup for more than two years now without any real issues - there are a few things you need to be aware ofthough.

 

You should not open Lightroom on yourdesktop computer and laptop at the same time. Both Lightroom instances will tryto lock the catalog file and you might end up with synchronization conflicts.If it does happen you can easily fix it by closing both Lightroom instances anddelete the conflicting file (typically a copy of your Lightroom catalog with a suffixat the filename).

 

The Catalog file will typically be synchedevery time you close Lightroom and the file lock is released. Once you closedLightroom on one machine, wait until the Catalog file is synchronized to thesecond computer before you open Lightroom on the second computer. Be careful ifthis happens while you are not connected to your LAN as it could take some timeto synchronize the Catalog file over the internet.

 

Preview files rendered on one computer willnot be synchronized to the other. In case you import photos to Lightroom onyour desktop computer, Lightroom will generate Previews. Once you closedLightroom on your desktop computer and then start Lightroom on your laptop,these Previews will automatically be rendered again on your laptop. This onlyhappens once and should not be too much of an issue.