Most of us know that a good headshot needs to be focused, have good lighting, show the actor looking directly into the lens (making strong eye contact with the viewer), and that the actor needs to look pretty much as they will when they walk into a casting director's office.
But there's something else. It is what I had my friend do as we took her shots. Like I said above - we need to be making good eye contact with the person who is looking at our headshot, but - and this is a huge "but" - we need to have something going on behind our eyes. No matter how good-looking we are, or how well the photo looks, technically, if there is only blankness behind our eyes, the headshot will not capture the viewer's attention.
Note: If a newbie director is making a short film and needs a cute male or female, he may only care that the actor looks "cute," but I'm really talking about professional casting directors and directors here. And they look for the magic going on behind the actor's eyes.
So back to my actress friend and her headshots. What I did was give her short little scenarios to think about while we were shooting. Since she was going to use them for a particular role, I gave her ones that might be part of that role.
But there are ones that could be used for any headshot shoot, for example: if you want to convey sadness, you might think about a good friend who has let you down, or if you want a great open smile, you might think about spotting the love of your life across a room and "lighting up" at the sight of his or her face.
I'm sure you could come up with other scenarios for other "looks." The point is if there is something actually going on behind your eyes, it will come across in the headshot. And that will make people (casters and directors) stop and take a second look. I would be prepared to have my own inner mini scenes to use as many headshot photographers don't know about them or how to use them - at least that's what I do for my own headshots.
Can you guess what I might be thinking in this headshot? It gets me called in for certain roles - which ones?
P.S. The friend that I shot the headshots for got called in for the role, and booked it!