Today’s Question: In response to the question about moving a Lightroom catalog, is it a bad idea to keep the catalog on an external hard drive so it can be moved among different computers more easily?
Tim’s Quick Answer: Putting your Lightroom catalog on an external hard drive provides a perfectly good solution for accessing your catalog from different computers. However, you’ll want to keep in mind that this approach can also significantly degrade overall performance in Lightroom.
More Detail: Lightroom tends to make extensive use of the Lightroom catalog, depending on your level of activity within Lightroom. Therefore, the overall performance for your computer when it comes to actually accessing the catalog files can have a tremendous impact on overall performance within Lightroom.
As a result, I generally recommend keeping your Lightroom catalog on a fast internal hard drive within your computer, to help maximize overall performance in Lightroom. In many cases (though there are certainly exceptions) an external hard drive will have considerably slower performance than an internal hard drive. In turn, that means that having your Lightroom catalog on an external hard drive can seriously degrade performance within Lightroom.
Storing your Lightroom catalog on an external hard drive can certainly be convenient in terms of being able to then access the catalog on different computers simply by moving the hard drive between those computers. However, because performance can be degraded significantly by this approach, I recommend only using this approach when doing so will provide a clear advantage to your workflow.
If you only need to access your Lightroom catalog on a different computer on a periodic basis, it might be better to copy the catalog each time you need to switch computers. But of course for some photographers it will be worth dealing with degraded performance in Lightroom in order to provide the convenience of accessing the catalog via a removable hard drive.
If you do decide to store your Lightroom catalog on an external hard drive, I highly recommend investing in a fast drive that makes use of a high-speed data connection to your computer.