Here I am with my team in Sharjah setting up the shoot for Xposure 2017. The logistics of shooting outside are complex and you have to find a way to control the lighting. I first used this technique in the the French Dordogne in 1991 when shooting my first Pirelli Canada in 1991. The reason I do this is that I want the figure within the awning to be completely in shadow so that I can light the model and then shoot with an iris shutter camera (like a Phase1 or a Hasselblad).
This is because a focal plane shutter can only shoot at 125th of a second before you get cut off either side of the image from the focal plane shutter . With the iris shutter one can shoot up to and over 1000th of a second, so that the background can be lightened or darkened, with the powerful flash on the figure over powering the daylight for a fraction of a second giving the dramatic effect. For example a clear blue midday sky with the sun overhead shadowing the model can become a deep blue or even a night time dramatic back drop. This is a bonus with modern digital photography which is much more light sensitive than film. Making the process, quicker and instantly viewable on a monitor, so you know what you are getting and can therefore adjust the camera settings.
Here is one of the finished shots, where the model was in the shadow of the overhead canopy but lit by the flash.