I teach an Available Portrait class and my favorite thing to show students is how to use almost any doorway to shoot a great portrait. The beauty of most doorways or even garage doors thresholds is that it’s very dark behind the subject. The dark background combined with the shade cast by the building almost always makes for incredible light and sparkling eyes.
This image was taken in a doorway to a warehouse type building. The sun was above and slightly behind the subject so as not to be directly on him.
I used a Panasonic GH4 with the 35-100mm Lumix lens at 72mm (144mm equivalent.) For me, it works best to zoom out from 135mm to 150mm to throw the background out of focus. Exposure was 1/640 sec at f/2.5 and ISO 400.
Remember to turn off any lights in the background and try to avoid bright objects in the background.–Mark Toal