In search of a method to resize these images, I found an easy way using Terminal.

  • Open up your Terminal app (can open Spotlight and search terminal).
  • cd into the desired image directory (e.g. if they are in your Pictures directory, you may: type "cd Pictures/").
  • Enter "sips -Z 1500 *.jpg" (with no "" marks).
  • Press enter. It will output every .jpg file in the directory you are in into a max of 1500 width or height.

Notes:

  • Change the "1500" to the max resolution you want.
  • It keeps the aspect ratio (-Z is the command for keeping aspect ratio).
  • Keep a back up of the full resolution images!