I had a small audience last evening when I was making some images of this telephone booth. One of the guys in my audience didn't believe me when I mentioned I could change the exposure of the background without changing the exposure of the foreground because I was using strobed light. So, I made this quick sequence to demonstrate and realised, half way through, it might also benefit people here at TPF: All are 1 stop steps in shutter speed, except the last which is just 1/3 stop...... all are at f/3.5. ISO 200 (D90, 1/200 sync). 1/200 1/100 1/60 1/30 1/15 1/10 Caught a fire fly in the 1/30 image.