Resizing Images for Slideshows – Mac

In my earlier article, Slideshows in a Digital Age. I talk about the need to resize images down to something that resembles the projectors inherent resolution. The idea is that since a good projector can only handle 1024 x 768 pixels, embedding a picture bigger than that only strains powerpoint and your hard drive — the projector still only puts 1024 x 768 pixels onto the screen.

So here’s a quick and easy approach for Mac users if you don’t want to fire up either Lightroom, Aperture or Photoshop:

  1. Copy the pictures you have chosen for your presentation into a folder on your desktop called “Resize.” Note that I said “Copy” — this is important since this process changes the files themselves and you don’t want to mess up your originals.
  2. In Finder, select all the images in “Resize” (you know about Ctrl-a, right?).
  3. Double click on one of the selected images — this will open them all in Preview.
  4. Select all the images in Preview (Again, Ctrl-a).
  5. In the Tools menu, click on “Adjust size.”
  6. Change to “pixels” in the dropdown to the right of “Width” and “Height.”
  7. Change “Width” to 1024 and make sure “Scale proportionally” is checked.
  8. After you click OK, you will see shrunk images.
  9. Do a File | Save ALL and you will now have a nice folder full of resized images.
  10. Use these images for your powerpoint.

This is a really quick and simple approach to making your powerpoints more efficient, faster loading and less likely to crash.