Back light to high light!

I learned more by accident than by plan how to use back lighting to high light my pictures.  Subjects in nature like butterflies don't pose and let me control the lighting.  Often, when photographing the combination of butterflies and flowers, I'll watch the activity for a while and then choose a flower on which to focus.  Then I'm ready when a butterfly comes along to load up with pollen.  The more translucent the butterfly, the more interesting the picture can be.  The butterfly, as beautiful as it is, doesn't contrast as well with the lighting from the front.