At some point most serious photographers make so many pictures that they will run out of space on their local hard drive. They will then want to put their images on an external hard drive. One of the most common questions we get from photographers is “how do I move my images to an external hard drive within Lightroom?”
This process is actually pretty straight forward in Lightroom but not terribly intuitive.
For many Lightroom users, they know better than to just move their images to their external hard drive. Lightroom is a catalog software. Basically this means that Lightroom references the file location. If you move that file behind without Lightroom knowing, Lightroom will have no idea where the image is. The image will then appear “offline or missing.”
If you have an image in Lightroom, that image should only be moved from within Lightroom.
To Move an image to an external drive, from within the Library module, press the “plus” button on the left navigation next to the Folders menu. Making sure your external hard drive is plugged in, select the drive. If you want to add a folder you can also do this.
Then within Lightroom, select the images and drag them into the new folder you have created. Lightroom will give you a warning that you are moving the files. Lightroom will then move the images from their present location to your external hard drive.
This will free up space on your local hard drive. Using Mosaic you can backup and connect to the contents of that external hard drive, even when you are not plugged in. This gives you anywhere access to you photos.
Most photographers will keep some of their photos on their local computer (depending on how many you take this could be the last year or the last week). Eventually when they are ready they will then move the files to an external hard drive.
Here is a quick video on how to move your files to an external hard drive using Lightroom.

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