Do you have master file JPGs imported into LR and you want to produce copies of those JPGs that are smaller in filesize than the original master files, or are you wanting to reduce the size of the master files, themselves—not something I’d recommend.
To create smaller-filesize-image copies of the master photos, use File / Export and resize to a smaller size and /or reduce the quality setting to a lower number. Of course each of these “solutions” will degrade the image as compared to the original.
Many thanks. These are JPEGS from RAW files entered into LR. I have reduced
the quality to 50% but couldn't see the smaller size adjustment
There are two ways to change the file size:
1. Reduce the quality setting like you have done. This will increase the compression at the cost of losing details/sharpness.
2. Reduce the number of pixels by making the image dimensions smaller.
How smaller are you looking to make the files?
What are you looking to do with them?