It was almost dark when I took this picture in San Marco Square in Venice. I used off-camera flash to illuminate the model, and because the members of my tour group had dispersed to photograph other subjects, I had no one to hold my flash. Therefore, i placed my camera backpack on the ground to the left of the model and nestled the flash into the fabric contours of the pack. To expose for this, I took a test shot and then tweaked the ambient exposure (for the background) using the exposure compensation feature built into the camera. To adjust the flash exposure, I used the flash exposure compensation feature in the flash unit. By using those two separate tools I was able to achieve the kind of lighting I wanted. My ISO was 1600 and the lens was a 24-105mm zoom. I had to use a tripod because the shutter speed was slow to expose the dark building.