When shooting a head shot outside I find that its helpful to put your subject in the open shade and use the sun as a side or back light. For these images of actress and Playboy® Playmate Carrie Stevens this is just what I did. At the back of the location we were at for the day, I found a great spot that would work for this setup. When placing somebody in the shade you will find that the light is very soft and you will not get a super sharp image so the trick is to pump the light up and make it a bit harder with the use of a reflector if you don’t have a strobe. The sun that is coming from the side or in my shots back light is use to separate the subject from the background.
Also with the use of a wider aperture F4.5 I was able to keep the background way out of focus. This helps make the viewers eye go to the sharpest part of the image which for a head shot should be the eyes. There was a banister that Carrie could place her arm on which helped work into my shots of her in the bright colored sweater.
In the other head shot I used her lovely full head of hair with a direct look to her face as my focal point.
When working outside take control of your light don’t just take a shot or you will end up with a snap that you might as well have taken with your phone. Please look to see if there are any trees coming out of the top of the head of your model, a sign of an ammeter photographer!