Oswald in the doorway: the blog of the Oswald Innocence Campaign, by Ralph Cinque

This is a valuable collage because the positions are very similar. 

Notice that on the right, her hand isn't getting to the top of that window. It isn't even reaching as high as the ledge of the car. In order to get to the top of the window, she would have to straighten her arm. She's not doing that on the left; her elbow is bent.