Hi, Kelly. I did, indeed, limit the current through the lamp. I had to replace a headlamp bulb because the low-beam filament burned out. So I had the lamp and decided that it'd be fun to get a shot of the still-good high-beam filament. I did power it with a variable power supply so that I could set the voltage/current. I wanted to see some of the filament via reflected light from the room but show some of it glowing. So this was fairly low power and a reasonably long exposure. I found that I liked the look of the gradient of temperatures across the filament. Jim H.
