Just Fred wrote:
When you export the file, you can specify file settings (JPEG, TIFF, PSD, etc.) quality and size. You can also adjust image sizing. These will all affect the size of the exported file.
Thanks, but what if I am not exporting the file at this time and it is just taking up space on my hard drive? I'd like to downsize the file which is stored on my hard drive before exporting it.