If you regularly work on two or more computers and carrying an external hard drive is not a problem, then consider putting your images and your Lightroom catalog on the external drive, so that you can move easily between the two.
If your catalog is currently on your internal hard drive, you will need to move it to the external drive:
- In LR, go to Edit (Lightroom on a Mac) > Catalog Settings, and on the General Tab note the location of your catalog.
- In Finder or Windows Explorer, move this folder to your external drive.
Now all you have to do is to tell LR to launch this catalog when it starts:
- With your external drive plugged in, hold down Ctl/ Cmd as you launch Lightroom to get the Select Catalog dialog. Click on Choose, and navigate to the .lrcat file inside your Lightroom Catalog folder on the external drive.
- Hit Continue.
That’s it! When you need to work on your other computer, plug in the drive, point to the catalog on this drive when you launch LR.
I would suggest a different approach if you ocassionally work images on your laptop when you are in the field photographing. See this post for more information.