This photo was made in an old ship factory in Amsterdam Noord (the NDSM Wharf). We picked a suitable old and faded green wall as the background, set up the lights, and started shooting.
The key lights are two Canon Speedlite 430EX strobes. They were pointed up into tall U-shaped corrugated cardboard sheets that were lined with aluminium foil to form DIY strip lights; both strobes were set to 1/4 power. The fill light was provided by a Speedlite 580EX-II at 1/16 power through a shoot-through umbrella.
I shot with my Canon EF 85mm f/1.8 USM on a Canon EOS 7D. The 1.6x crop factor makes this a very nice portrait lens. The aperture was f/8 to get sufficiently deep depth of field and sharp results, and the shutter speed of 1/250 second ensured that no available light got onto the sensor.
Here is a wide shot that shows the setup. I used the 7D as the master, and I was surprised how well it worked. Because I used my 85mm f/1.8 I could move back a little (compared to my standard 17-55mm zoom), which made the slave strobes more into the "field of view" of the popup flash. The 430EX's "looked" at Marit instead of my camera, so I added some aluminium foil to bounce the master flash into their IR sensors.
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