A Computer Darkroom Tutorial

If asked to identify their two most sought after features for Adobe Lightroom I think most users would pick the management of off-line images and synchronising of laptop/desktop computer libraries. Unfortunately, neither seems likely to be included anytime soon. So, how do we overcome what are very real problems for many photographers?


Well, the good news is that a lot of the infrastructure required for managing off-line or remote images is already in place, but it's either hidden or not very elegantly presented. Nevertheless, by using this infrastructure it's fairly easy to reference off-line images, and get them back into the library again when required. This same infrastructure can also be used as a pseudo-synchronised library (i.e. a Unitary Library).

Important Background Information on Lightroom Library

A Library folder with the default name Lightroom is automatically created the first time that the application is launched, and will most likely be located on your boot disk at Users/username/Pictures (Mac OSX) or My Pictures\Lightroom (Windows XP). A quick check of this folder will probably show a number of files, subfolders or packages, but for the purposes of this tutorial we're only really interested in the managed photos folder and the file named - Lightroom Library.aglib.

The Managed Photos folder, will contain any images that may already have been imported into Lightroom via the Copy, Move or Copy as DNG options. Since this folder usually contains images associated with the managed library  this folder is usually referred to as the Managed Photos folder. Actually, if you do have the Managed Photos subfolder inside the Lightroom folder and it contains images, then now is a good time to drag it out. Obviously this may break the links between the images and thumbnails, but I will show how this can be fixed later. Once moved it's also important that the application knows that the Managed Photos folder is now located outside of the Lightroom folder. Therefore, I suggest that you update the Lightroom Preferences as demonstrated by the example shown in Figure 1 below.


Figure 1 - Telling Lightroom where to place Managed Photos

The Managed Photos folder can be located pretty much anywhere, which includes external disk drives or even a network server. The folder can even given a name more in keeping with your normal folder naming convention. The important point to keep in mind here is, that by keeping the Managed Photos folder outside of the Lightroom folder you are making it much easier to transport and subsequently back-up the library independently of your images.


Figure 2 - Lightroom with existing image Library

Creating a Unitary Library

Step 1 - Moving the Library

At present, the simplest approach to running Lightroom on multiple computers is to have only one Lightroom library (i.e. Unitary Library), but share it amongst these computers. For this purpose I use a SmartDisk FireLite 100GB FireWire drive, but any compact portable disk drive is suitable. This particular disk drive is powered by the FireWire port of my Apple PowerBook, is compact and lightweight. USB 2 versions are also available. At a spin speed of 5200 rpm it's not the fastest disk drive in the world, but not having to connect it to an electrical supply is a big advantage when working in the field.


SmartDisk FireLite Portable Disk Drive

The Unitary Library (i.e. the folder named Lightroom and its contents) should be placed onto a portable disk drive (see figure 3 below). To do so simply move the Lightroom folder from the computer disk drive across to the portable disk drive. If the library is new it will take only a few seconds to move. However, if you have already imported some images into Lightroom it will take a little longer. The actual time taken depends upon the number of thumbnails stored in the Library. So, relocating the library onto the portable disk while it's still relatively small has its advantages.

It's also worth mentioning that, if space is tight on your laptop it might be worthwhile using the portable disk drive as your image store for work-in-progress images. Likewise, any images that you need to access regularly when away from your main workstation. I'm not suggesting it as a permanent store, but one that is used for short term portable storage. Once you have access to the desktop computer the image folder can be moved across to more secure and faster disk drives.


Figure 3 - Moving the Lightroom Library to a Portable Disk Drive

Step 2 - Accessing the relocated Library

Lightroom Beta 4 can still only access one library at a time, so accessing the version now installed on the portable disk drive requires a little trickery.

  • Hold down the Option (Mac OS) or Ctrl (Win XP) key and launch Lightroom.

  • Browse to the portable disk drive

  • Open the Lightroom folder and select the file named Lightroom Library.aglib (Note: the file extension isn't normally visible in Win XP)

  • Hit the Choose button and presto you have reactivated your old Library (see Figure 4).


Figure 4 - Selecting the relocated Library

Note: this description for relocating the library was first published by Michael Reichmann at Luminous Landscape

When Lightroom reopens you may find that your images now have a "?" symbol on the top right corner (Figure 5 below). If  the "?" mark symbol is present then this is a sign that the links between the library thumbnails and actual images have been broken and that you'll need to repair them. However, more often than not Lightroom will reopen with the links back to the original images still in place. If the links are still intact the thumbnails will look as they do in Figure 2 above (i.e. no "?" symbol).


Figure 5 - Lightroom has lost the link to your images

Images with the "?" symbol in the top right corner are orphaned and cannot be edited in Lightroom until re-linked with the library. However, so long as the original thumbnail process was allowed to complete, then  it's still possible to apply Keywords, Ratings. etc. Likewise, it's also possible to create and present slideshows and web galleries. It's even possible to print contact sheets.

Earlier I indicated that Lightroom could only access one library, but this should not be construed as meaning that you can have only one library. Actually, you can have as many libraries as you wish. Space permitting, they can all be stored on the same portable disk, although each must have a unique name. To open a alternative library simply hold down the Option key (Mac) or Ctrl key (Windows) when launching Lightroom and a dialog similar to the following will be displayed.


Figure 6 - Picking a Library

Step 3 - Locating your images

In the event that the links between the library and images were broken when you moved the Lightroom folder, then re-establishing these links is the next step. Finding the images again is actually very simple.

  • Click on the "?" symbol of the first image and Lightroom will inform you exactly where it was originally located. In the example shown in Figure 7 below you can see that the selected image was originally located on the main disk drive of my PowerBook.


Figure 7 - Finding your Images

  • If the identified disk drive is off-line you should reconnect it. Generally, this is all that is needed for Lightroom to automatically re-establish the link and make the "?" disappear. If it doesn't then hit the Locate button - Lightroom will immediately open an OS dialog and highlight the relevant image (see Figure 8).


Figure 8 - Selecting the Image

  • If Lightroom doesn't automatically locate the image then you will have to do it manually using Folder or List view as shown above. It's important that you find and select the same image as was selected in the Lightroom window otherwise the previews could easily become corrupted.

  • Once the correct image is found hit the Select button and the dialog will close.

On return to the Lightroom you'll notice that the "?" symbols begins to disappear from the thumbs. Once the "?" disappears it will be possible to begin editing the images within the Develop module.

If you disconnect the portable disk Lightroom will loose track of where the library was and will display a dialog similar to the following when launching the application:



Figure 7 - Lightroom has lost the Library

As can be seen in the screenshot Lightroom advises you of where the Library was last located, which is generally all that is needed when using the Mac platform. However, Windows seems a little more prone to loosing  the Library when the user moves it using Explorer. If this occurs, then you will need to use the Locate Library button to navigate to the new  library location. The Use Default Library option creates a completely new library, and should only be used when that is what you want to do.

Off-line Storage

If you've got this far then you'll be glad to know that all the difficult steps are finished. I've demonstrated how it's possible to relocate a Lightroom Library and subsequently re-link any orphaned images. However, it's also possible to do it the other way round. That is to say, relocate the image folders. The process of finding archived or even orphaned images is the same as described above. For example, say the original folder with images has also been relocated to an off-line storage device or DVD. Lightroom will identify all such images in the same way as I described above (i.e. the  "?" symbol in the top right corner of the thumbnail), which when clicked opens the same dialog shown in figure 7 above. Again, the dialog includes the name of the volume, folder and image name, so finding the correct disk should be relatively easy. Once the disk drive is reconnected Lightroom will automatically re-establish the links between the thumbnails and all of images stored on the disk.

Finally, by combining the principal of Unitary Library and Off-line storage as described above you can manage very large numbers of images in multiple locations. Hopefully, the methods described above will be made redundant in the near future, but in the meantime it's probably the easiest way to manage and access large numbers of images quickly.

Remember Rule 5 - Enjoy!

Adobe Community Professional

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