The cache is the storage area reserved for files, multimedia, data, and instructions that help in speeding up the performance of the software. Lightroom too uses cache, which takes up valuable space over time, often causing errors and delays in your workflow. Knowing how to clear Lightroom cache will help you free up some space and make it run smoothly.
Cache begins storing data as soon as you start using Lightroom for the first time. All this gathered data is used to reduce load time. However, this data is temporary and not very crucial. Therefore you can get rid of it every now and then to clear up usable space.
Emptying the cache is an important step to resolve sluggish speed and bugs in Lightroom. Before moving on to the procedure to purge the cache, let's understand the types of cache in Lightroom and why the need arises to delete them.
There are four types of cache that are stored in Lightroom.
To help display your catalog images quickly, Lightroom stores their previews in the Camera Raw cache folder. If you increase its size, it can store a higher number of previews. However, if you habitually add hundreds of RAW images to Lightroom, this folder may unnecessarily fill up and clog your disk space.
Video cache is similar to the Camera Raw cache as it stores Video previews to load the files quickly.
Images in Lightroom are shown in the form of thumbnails. For instance, the Grid view, Filmstrip view, survey view, and navigation panel preview all have image thumbnails. These thumbnails are displayed with the help of Previews that Lightroom generates
One thing worth mentioning here is that every time you start Lightroom, the preview caches are produced. Therefore, we recommend you empty this folder only if it is required as it could halt Lightroom.
Smart previews are smaller in size than regular previews. If your original images are stored on the external hard drive that is not connected to your computer, Lightroom will use the smart previews for editing or any other work that you want to do with them.
Let’s over the process of clearing each type of cache we’ve discussed.
Deleting the previews and smart previews cache is a different process. Cache for Lightroom’s Previews are stored in a file named [Catalog name] Previews.lrdata, and those for Smart previews are stored in a file named [Catalog name] Smart Previews.lrdata. Lightroom stores both the cache folders besides the catalog folder by default.
You can delete these caches by deleting these corresponding files in the Finder on Mac or in the Explorer on Windows. However, we recommend quitting Lightroom before you purge these files.
Note: Lightroom is designed to build previews as soon as you start it again. Therefore, it may take some time to develop and upload new previews. A new previews.lrdata file will also be created, which will once again start to fill after Lightroom resumes the preview building process.
As for the Smart Previews cache, it will start getting generated when you create a new smart preview in Lightroom.
Remember to empty your Recycle Bin on Windows or Trash on Mac after purging the cache to free up your disk space.
The need to purge the caches may arise due to many reasons. Two of the most common reasons are:
Depending upon the kind of your work, your Lightroom cache may take up a lot of space on your disk. As space is taken up by the unnecessary cache files, it is wise to delete your cache once in a while. In this way, a lot of disk space may be cleared, and Lightroom will only build previews with the images that are currently in your catalog.
Stuffed cache folders often cause annoying errors while you are running Lightroom. It may show an error during the import, like not generating previews or missing all of them.
Lightroom may notify you to close the program as the preview cache is unreadable. In such cases, deleting the cache may resolve your issues. You can also use a plugin that handles your cache automatically.
If you feel apprehensive about deleting Lightroom cache, know that it is a safe process that won’t affect your original images, presets, or Develop module settings. You might notice a temporary issue in speed after deleting the cache, which will resolve once all your previews are rebuilt.