See Before and After with Photoshop Elements
by Jack
(Scottsdale)
Alt/Option-click the Eye Icon next to the Background Layer
You can also use the Undo History palette
Q: How do I toggle back and forth from my original to present to see the difference in the changes I made?
A: Great question Jack. There's a couple ways you can do it.
The technique I use most of the time is done in the Layers Palette since I almost always use Layers to do my changes on. For this method you have to be sure that your Background Layer is exactly the same as it was when you first opened the photo, with no changes applied directly to it.
What you do to see the Before is hold down the Alt (Mac:Option) key and click on the Eye icon next to your Background Layer. That will turn the visibility of all the other Layers off (the eye icons next to them will disappear). To see the Present state do the same thing. Hold down the alt/option key and click the eye icon next to the Background Layer.
The other method you can use calls for the Undo History palette. Go up to the Window menu and choose Undo History to make that palette visible.
At the top of the palette is a thumbnail of your image with its' name next to it. Below are all the changes you made listed in the order that you made them. The bottom item is the last change you made.
If you click on the thumbnail at the top, your photo will temporarily revert to its Original state. To return to the Present state just click on the bottom item in the palette list.