After I edit a image how do I delete the secret original copy

There's an unacknowledged bug in iPhoto 5 where many users are not having
changes in
sharpness saved. Apple notes that screen aliasing may make your changes
imperceiveable.

http://docs.info.apple.com/article.html?artnum=301425

However, there really is an issue with sharpness changes not saving. There is a
work
around. First make sure the sharpness slider is your last edit. (Other sliders
can work
against sharpness.) Then, as the last step, press the number "2" key. This blows
the image
up to full size. Then scroll up or down on the image. It only has to move a tiny
bit. Now
your changes will be saved.

Kevin