I am starting a photography studio and bought two softboxes and two umbrellas. In the softboxes, I have 5 florescent bulbs of 45 watts in each and one 45 watt bulb in each of the umbrellas. I have a Canon 40D and a 50mm 1:1.8 lens, and also a 70-200mm 2.8 lens. I would like to shoot 100 ISO and f8.0, but my shutter speed is hitting about 1/30. Do I need more powerful bulbs? How do I shoot at my desired settings, or what settings can I use to achieve that softness and lighting contrast with shadows to my portraits?